-<Chapter Id="commands">
-<Title>Commands</Title>
+<chapter Id="sql-commands">
+<title>Commands</title>
-<Para>
-</Para>
+<para>
+</para>
&alterTable;
&alterUser;
&createTable;
&createTrigger;
&createType;
+&createUser;
+&createView;
+&declare;
+&delete;
&dropFunction;
+&reset;
+&revoke;
+&rollback;
&select;
+&set;
+&show;
+&update;
-</Chapter>
+</chapter>
+
+<chapter Id="sql-functions">
+<title>SQL Functions</title>
+
+<para>
+</para>
+
+¤tDate;
+¤tTime;
+¤tTimestamp;
+¤tUser;
+
+</chapter>
<!-- Keep this comment at the end of the file
Local variables:
--- /dev/null
+<REFENTRY ID="SQL-CREATEUSER-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ CREATE USER
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ CREATE USER
+ </REFNAME>
+ <REFPURPOSE>
+ Creates account information for a new user
+ </REFPURPOSE>
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+
+ CREATE USER<REPLACEABLE CLASS="PARAMETER"> username</REPLACEABLE>
+ [WITH PASSWORD <REPLACEABLE CLASS="PARAMETER">password</REPLACEABLE>]
+ [CREATEDB | NOCREATEDB]
+ [CREATEUSER | NOCREATEUSER]
+ [IN GROUP <REPLACEABLE CLASS="PARAMETER">groupname</REPLACEABLE> [, ...] ]
+ [VALID UNTIL '<REPLACEABLE CLASS="PARAMETER">abstime</REPLACEABLE>']
+
+
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-CREATEUSER-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">username</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The name of the user.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">password</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The WITH PASSWORD clause sets the user's password within
+ the "<filename>pg_shadow</filename>" table. For this reason,
+ <filename>"pg_shadow</filename>" is no
+ longer accessible to the instance of PostgreSQL that the
+ PostgreSQL user's password is initially set to NULL.
+ <comment>The text here has got garbled.</comment>
+ When a
+ user's password in the "<filename>pg_shadow</filename>"
+ table is NULL, user
+ authentication proceeds as it historically has (HBA,
+ PG_PASSWORD, etc). However, if a password is set for a
+ user, a new authentication system supplants any other
+ configured for the PostgreSQL instance, and the password
+ stored in the "<filename>pg_shadow</filename>" table is used
+ for authentication.
+ For more details on how this authentication system
+ functions see pg_crypt(3). If the WITH PASSWORD clause is
+ omitted, the user's password is set to the empty
+ string with equates to a NULL value in the authentication
+ system mentioned above.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue> CREATEDB/NOCREATEDB</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ These clauses define a user's ability to create databases.
+ If CREATEDB is specified, the user being defined will
+ be allowed to create his own databases. Using NOCREATEDB
+ will deny a user the ability to create databases. If this
+ clause is omitted, NOCREATEDB is used by default.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>CREATEUSER/NOCREATEUSER</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ These clauses determine whether a user will be permitted to
+ create new
+ users in an instance of PostgreSQL.
+ Omitting this clause will set the user's value of this
+ attribute to be NOCREATEUSER.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">groupname</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ A name of a group into which to insert the user as a new member.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">abstime</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The VALID UNTIL clause sets an absolute time after which the
+ user's PostgreSQL login is no longer valid. Please note that
+ if a user does not have a password defined in the
+ "<filename>pg_shadow</filename>"
+ table, the valid until date will not be checked
+ during user authentication. If this clause is omitted,
+ a NULL value is stored in "<filename>pg_shadow</filename>"
+ for this attribute,
+ and the login will be valid for all time.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-CREATEUSER-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>CREATE USER</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ Message returned if the command completes successfully.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>ERROR: removeUser: user "<replaceable class="parameter">username</replaceable>" does not exist</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ if "<replaceable class="parameter">username</replaceable>" not found.
+ </PARA>
+ <comment>I don't understand this and I don't know how to get
+this error message.</comment>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-CREATEUSER-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ CREATE USER will add a new user to an instance of PostgreSQL.
+ </PARA>
+ <PARA>
+ The new user will be given a <filename>usesysid</filename> of:
+ '<command>SELECT MAX(usesysid) + 1 FROM pg_shadow</command>'.
+ This means that
+ PostgreSQL users' <filename>usesysid</filename>s will not
+ correspond to their operating
+ system(OS) user ids. The exception to this rule is
+ the '<literal>postgres</literal>' user, whose OS user id
+ is used as the
+ <filename>usesysid</filename> during the initdb process.
+ If you still want the
+ OS user id and the <filename>usesysid</filename> to match
+ for any given user,
+ use the "createuser" script provided with the PostgreSQL
+ distribution.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CREATEUSER-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA>
+ CREATE USER statement is a PostgreSQL language extension.
+ </PARA>
+ <para>
+ Use DROP USER or ALTER USER statements to remove or modify a user
+ account.</para>
+ <para>
+ Refer to the <filename>pg_shadow</filename> table for further information.
+ </para>
+ <programlisting>
+ Table = pg_shadow
+ +--------------------------+--------------------------+-------+
+ | Field | Type | Length|
+ +--------------------------+--------------------------+-------+
+ | usename | name | 32 |
+ | usesysid | int4 | 4 |
+ | usecreatedb | bool | 1 |
+ | usetrace | bool | 1 |
+ | usesuper | bool | 1 |
+ | usecatupd | bool | 1 |
+ | passwd | text | var |
+ | valuntil | abstime | 4 |
+ +--------------------------+--------------------------+-------+
+ </programlisting>
+ </REFSECT2>
+
+ <REFSECT1 ID="R1-SQL-CREATEUSER-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ Create a user with no password:
+ </PARA>
+ <ProgramListing>
+ CREATE USER jonathan
+ </ProgramListing>
+ <PARA>
+ Create a user with a password:
+ </PARA>
+ <ProgramListing>
+ CREATE USER davide WITH PASSWORD jw8s0F4
+ </ProgramListing>
+ <para>
+ Create a user with a password, whose account is valid until the end of 2001.
+ Note that after one second has ticked in 2002, the account is not
+ valid:
+ </para>
+ <ProgramListing>
+ CREATE USER miriam WITH PASSWORD jw8s0F4 VALID UNTIL 'Jan 1 2002'
+ </ProgramListing>
+ <para>
+ Create an account where the user can create databases:
+ </para>
+ <ProgramListing>
+ CREATE USER manuel WITH PASSWORD jw8s0F4 CREATEDB
+ </ProgramListing>
+
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-CREATEUSER-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CREATEUSER-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ There is no CREATE USER statement in SQL92.
+ </PARA>
+</REFENTRY>
+
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-CREATEVIEW-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ CREATE VIEW
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ CREATE VIEW
+ </REFNAME>
+ <REFPURPOSE>
+Constructs a virtual table
+ </REFPURPOSE>
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+ CREATE VIEW <REPLACEABLE CLASS="PARAMETER">view</REPLACEABLE>
+ AS SELECT <REPLACEABLE CLASS="PARAMETER">query</REPLACEABLE>
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-CREATEVIEW-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">view</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The name of a view to be created.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">query</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+An SQL query which will provide the columns and rows of the view.
+ </PARA>
+ <PARA>
+ Refer to the SELECT statement for more information
+ about valid arguments.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-CREATEVIEW-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>CREATE</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The message returned if the view is successfully created.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>
+ WARN amcreate: "<replaceable class="parameter">view</replaceable>" relation already exists
+ </ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ This error occurs if the view specified already exists in the database.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>NOTICE create: attribute named "<replaceable class="parameter">column</replaceable>" has an unknown type</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The view will be created having a column with an unknown type
+ if you do not specify it. For example, the following command gives
+ an error:
+ <programlisting>
+ CREATE VIEW vista AS SELECT 'Hello World'
+ </programlisting>
+ whereas this command does not:
+ <programlisting>
+ CREATE VIEW vista AS SELECT 'Hello World'::text
+ </programlisting>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-CREATEVIEW-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ CREATE VIEW will define a view of a table. This view is
+ not physically materialized. Specifically, a query
+ rewrite retrieve rule is automatically generated
+ to support retrieve operations on views.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CREATEVIEW-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA>
+ Use the DROP VIEW statement to drop views.
+ </PARA>
+ </refsect2>
+
+ <REFSECT2 ID="R2-SQL-CREATEVIEW-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Bugs
+ </TITLE>
+ <para>
+ Currently, views are read only.
+ </para>
+ </REFSECT2>
+
+ <REFSECT1 ID="R1-SQL-CREATEVIEW-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ Create a view consisting of all Comedy films:
+ </PARA>
+ <ProgramListing>
+ CREATE VIEW kinds AS
+ SELECT *
+ FROM films
+ WHERE kind = 'Comedy';
+
+ SELECT * FROM kinds;
+
+ code |title |did| date_prod|kind |len
+ -----+-------------------------+---+----------+----------+------
+ UA502|Bananas |105|1971-07-13|Comedy | 01:22
+ C_701|There's a Girl in my Soup|107|1970-06-11|Comedy | 01:36
+ </ProgramListing>
+
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-CREATEVIEW-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CREATEVIEW-5">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ SQL92 specifies some additional capabilities for the CREATE VIEW statement:
+ </PARA>
+ <programlisting>
+ CREATE VIEW <replaceable class="parameter">view</replaceable> [ <replaceable class="parameter">column</replaceable> [, ...] ]
+ AS SELECT <replaceable class="parameter">expression</replaceable> [AS <replaceable class="parameter">colname</replaceable>] [, ...]
+ FROM <replaceable class="parameter">table</replaceable>
+ [WHERE <replaceable class="parameter">condition</replaceable>]
+ [ WITH [ CASCADE | LOCAL ] CHECK OPTION ]
+ </programlisting>
+
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>CHECK OPTION</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA> This option is to do with updatable views.
+ All INSERTs and UPDATEs on the view will be
+ checked to ensure data satisfy the view-defining
+ condition. If they do not, the update will be rejected.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>LOCAL</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ Check for integrity on this view.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>CASCADE</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ Check for integrity on this view and on any dependent
+ view. CASCADE is assumed if neither CASCADE nor LOCAL is specified.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
+ </refsect1>
+</REFENTRY>
+
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-CURRENT-DATE-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ SQL_CURRENT_DATE
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Functions</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ SQL_CURRENT_DATE
+ </REFNAME>
+ <REFPURPOSE>
+- returns the current date, (i.e "today").
+ </REFPURPOSE>
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+ CURRENT_DATE
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-DATE-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+<VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>None</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-DATE-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>Returns "<replaceable class="parameter">today</replaceable>"</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-DATE-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ The niladic CURRENT_DATE function has a data type of
+ DATE and returns the date at the time that it is run.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-DATE-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA>
+ Refer to SET DATESTYLE for further information about date format.
+ </PARA>
+ </REFSECT2>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-DATE-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ Insert the date of insertion into a row:
+ </PARA>
+ <ProgramListing>
+ INSERT INTO films
+ VALUES ('TM999','Ben Hur',105,CURRENT_DATE,'Action',NULL);
+ </ProgramListing>
+
+ <PARA>
+ Display CURRENT-DATE:
+ </PARA>
+ <ProgramListing>
+ SELECT CURRENT_DATE AS today;
+
+ today
+ ------------
+ 1998-03-31
+
+ </ProgramListing>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-DATE-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-DATE-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ Full compatibility.
+ </PARA>
+ </refsect2>
+ </refsect1>
+</REFENTRY>
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-CURRENT-TIME-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ SQL_CURRENT_TIME
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Functions</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ SQL_CURRENT_TIME
+ </REFNAME>
+ <REFPURPOSE>
+ - returns the current local time, (i.e "now").
+ </REFPURPOSE>
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+ CURRENT_TIME
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIME-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>None</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIME-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>Returns "<replaceable class="parameter">now</replaceable>"</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-TIME-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ The niladic CURRENT_TIME function has a data type of
+ TIME and returns the local time when it is run.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIME-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA> Refer to the SET TIME ZONE statement for a further description
+ of local time.
+ </PARA>
+ </REFSECT2>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-TIME-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>Display CURRENT_TIME:
+ </PARA>
+ <ProgramListing>
+ SELECT CURRENT_TIME AS now;
+
+ now
+ -----------
+ 17:41:31+02
+
+ </ProgramListing>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-TIME-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIME-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ SQL92 specifies some additional capabilities for CURRENT_TIME:
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>
+ CURRENT_TIME [ (<replaceable class="parameter">scale</replaceable>) ]</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The optional scale for CURRENT_TIME, if specified, is an
+ unsigned integer representing the number of digits in the
+ optional seconds fraction of the time value represented
+ by the function.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+</REFENTRY>
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-CURRENT-TIMESTAMP-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ SQL_CURRENT_TIMESTAMP
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Functions</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ SQL_CURRENT_TIMESTAMP
+ </REFNAME>
+ <REFPURPOSE>
+ returns the current timestamp, (i.e the
+ date "today" concatenated with time "now").
+ </REFPURPOSE>
+
+
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <synopsis>
+ CURRENT_TIMESTAMP
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIMESTAMP-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>None</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIMESTAMP-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>Returns "<replaceable class="parameter">today</replaceable>" and "<replaceable class="parameter">now</replaceable>".</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-TIMESTAMP-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ The niladic CURRENT_TIMESTAMP function has a data type of
+ TIMESTAMP and returns the date and local time at which it is run.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIMESTAMP-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA>
+ Refer to the SET TIME ZONE statement for a further description
+ of local time.
+ </PARA>
+
+
+ </REFSECT2>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-TIMESTAMP-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ Display CURRENT_TIMESTAMP:
+ </PARA>
+ <ProgramListing>
+ SELECT CURRENT_TIMESTAMP AS date_and_time;
+
+ date_and_time
+ ----------------------
+ 1998-03-31 07:41:21-08
+ </ProgramListing>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-TIMESTAMP-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-TIMESTAMP-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ SQL92 specifies some additional capabilities for CURRENT_TIMESTAMP:
+ </PARA>
+
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>CURRENT_TIMESTAMP [ (<replaceable class="parameter">scale</replaceable>) ]</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The optional scale for CURRENT_TIMESTAMP, if specified, is an
+ unsigned integer representing the number of digits in the
+ optional seconds fraction of the time value represented
+ by the function.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </para>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </refsect2>
+ </refsect1>
+</REFENTRY>
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-CURRENT-USER-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ SQL_CURRENT_USER
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Functions</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ SQL_CURRENT_USER
+ </REFNAME>
+ <REFPURPOSE>
+ - returns the current user name.
+ </REFPURPOSE>
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+ CURRENT_USER
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-USER-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>None</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-USER-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>The name of the current user.</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-USER-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ The niladic CURRENT_USER function returns a string of type "name"
+ whose value represents a user name identification.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-USER-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA>
+ Data type "name" is a non-standard 31-character type for storing
+ system identifiers.
+ </PARA>
+ </REFSECT2>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-USER-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ Display CURRENT_USER
+ </PARA>
+ <ProgramListing>
+ SELECT CURRENT_USER AS who_am_i;
+
+ who_am_i
+ ------------
+ jose
+ </ProgramListing>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-CURRENT-USER-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-CURRENT-USER-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ SQL92 specifies some additional niladic USER functions:
+ </PARA>
+ <variablelist>
+ <varlistentry>
+ <term>CURRENT_USER / USER</term>
+ <listitem>
+ <para>
+ USER is a synonym for CURRENT_USER.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>SESSION_USER</term>
+ <listitem>
+ <para>
+ The SESSION_USER function returns the SQL-session user name.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>SYSTEM_USER</term>
+ <listitem>
+ <para>
+ The SYSTEM_USER function returns the database's initial default user.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ <para>
+ A niladic USER function returns a SQL_TEXT character string whose
+ value represents a user name.
+ </para>
+ </refsect2>
+ </refsect1>
+</REFENTRY>
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-DECLARESTATEMENT-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ DECLARE STATEMENT
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ DECLARE STATEMENT
+ </REFNAME>
+ <REFPURPOSE>
+ Declares a cursor
+ </REFPURPOSE>
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+ DECLARE <replaceable class="parameter">cursor</replaceable> [ BINARY ]
+ FOR SELECT <replaceable class="parameter">query</replaceable>
+ </SYNOPSIS>
+ <REFSECT2 ID="R2-SQL-DECLARESTATEMENT-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>BINARY</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The BINARY keyword causes the cursor to fetch data in binary
+ rather than in ASCII format.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">cursor</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The cursor's name.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">query</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ An SQL query which will provide the rows to be governed by the
+ cursor.
+ </PARA>
+ <PARA>
+ Refer to the SELECT statement for further information about
+ valid arguments.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-DECLARESTATEMENT-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>SELECT</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The message returned if the SELECT is run successfully.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue>NOTICE
+ BlankPortalAssignName: portal "<replaceable class="parameter">cursor</replaceable>" already exists</ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ This error occurs if cursor "<replaceable class="parameter">cursor</replaceable>" is already declared.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+ </REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-DECLARESTATEMENT-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ DECLARE allows a user to create cursors, which can be used to retrieve
+ a small number of rows at a time out of a larger query. Cursors can return
+ data either in ASCII or in binary foramt.
+ </PARA>
+ <PARA>
+ Normal cursors return data in ASCII format. Since
+ data is stored natively in binary format, the system must
+ do a conversion to produce the ASCII format. In addition,
+ ASCII formats are often larger in size than binary format.
+ Once the information comes back in ASCII, the client
+ application often has to convert it to a binary format to
+ manipulate it anyway.
+ </PARA>
+ <PARA>
+ BINARY cursors give you back the data in the native binary
+ representation. So binary cursors will tend to be a
+ little faster since they suffer less conversion overhead.
+ For example, for an integer column, you get a C integer number like ^A
+ using a binary cursor, while you get a string value like '1'
+ using the non binary cursor.
+ </PARA>
+ <PARA>
+ However, ASCII is architecture-neutral whereas binary
+ representation can differ between different machine architectures.
+ Therefore, if your client machine and server machine use different
+ representations, you will probably not want your data returned in
+ binary format.
+ Again, if you intend to display the data in
+ ASCII, getting it back in ASCII will save you some
+ effort on the client side.
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-DECLARESTATEMENT-3">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Notes
+ </TITLE>
+ <PARA>
+ Cursors are only available in transactions.
+ </PARA>
+ <PARA>
+ PostgreSQL does not have an explicit <command>OPEN cursor</command>
+ statement; a cursor is considered to be open when it is DECLAREd.
+ </PARA>
+ </REFSECT2>
+ </refsect1>
+
+ <REFSECT1 ID="R1-SQL-DECLARESTATEMENT-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ To declare a cursor:
+ </PARA>
+ <ProgramListing>
+ DECLARE liahona CURSOR
+ FOR SELECT * FROM films;
+ </ProgramListing>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-DECLARESTATEMENT-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-DECLARESTATEMENT-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ SQL92 specifies some additional capabilities for the DECLARE statement:
+ </PARA>
+ <synopsis>
+ DECLARE cursor [ INSENSITIVE ] [ SCROLL ] CURSOR
+ FOR SELECT expression
+ [ ORDER BY column [, ... ] [ ASC | DESC ]
+ [ FOR { READ ONLY | UPDATE [ OF column [, ...] ] } ]
+ </synopsis>
+ <variablelist>
+ <varlistentry>
+ <term></term>
+ <listitem>
+ <variablelist>
+ <varlistentry>
+ <term>INSENSITIVE</term>
+ <listitem>
+ <para>
+ UPDATE and DELETE CURRENT operations are not allowed
+ if the cursor is declared to be INSENSITIVE.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>SCROLL</term>
+ <listitem>
+ <para>
+ If SCROLL is not specified, only FETCH NEXT will be allowed.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>FOR READ ONLY/UPDATE</term>
+ <listitem>
+ <para>
+ If READ ONLY is specified, UPDATE/DELETE CURRENT operations
+ will not be allowed.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+</REFENTRY>
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
--- /dev/null
+<REFENTRY ID="SQL-DELETE-1">
+ <REFMETA>
+ <REFENTRYTITLE>
+ DELETE
+ </REFENTRYTITLE>
+ <REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+ </REFMETA>
+ <REFNAMEDIV>
+ <REFNAME>
+ DELETE
+ </REFNAME>
+ <REFPURPOSE>
+ Deletes rows from a table
+ </REFPURPOSE>
+
+
+ <REFSYNOPSISDIV>
+ <REFSYNOPSISDIVINFO>
+ <DATE>1998-04-15</DATE>
+ </REFSYNOPSISDIVINFO>
+ <SYNOPSIS>
+ DELETE FROM <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE> [ WHERE <REPLACEABLE CLASS="PARAMETER">condition</REPLACEABLE> ]
+ </SYNOPSIS>
+
+ <REFSECT2 ID="R2-SQL-DELETE-1">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Inputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">table</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ The name of an existing table.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue><replaceable class="parameter">condition</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ This is an SQL selection query which returns the rows which
+ are to be deleted.
+ </PARA>
+ <PARA>
+ Refer to the SELECT statement for further description
+ of the WHERE clause.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+
+ <REFSECT2 ID="R2-SQL-DELETE-2">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ Outputs
+ </TITLE>
+ <PARA>
+ </PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ <VARIABLELIST>
+ <VARLISTENTRY>
+ <TERM>
+ <ReturnValue> DELETE <replaceable class="parameter">count</replaceable></ReturnValue>
+ </TERM>
+ <LISTITEM>
+ <PARA>
+ Message returned if items are successfully deleted. The
+ <replaceable class="parameter">count</replaceable> is the number
+ of rows deleted.
+ </PARA>
+ <PARA>
+ If <replaceable class="parameter">count</replaceable> is 0,
+ no rows are deleted.
+ </PARA>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </variablelist>
+ </LISTITEM>
+ </VARLISTENTRY>
+ </VARIABLELIST>
+ </REFSECT2>
+</REFSYNOPSISDIV>
+
+ <REFSECT1 ID="R1-SQL-DELETE-1">
+ <REFSECT1INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT1INFO>
+ <TITLE>
+ Description
+ </TITLE>
+ <PARA>
+ DELETE removes rows which satisfy the WHERE <replaceable class="parameter">condition</replaceable>,
+ from the specified table.
+ </PARA>
+ <PARA>
+ If the <replaceable class="parameter">condition</replaceable> is absent,
+ the effect is to delete all rows in the table.
+ The result is a valid, but empty table.
+ </PARA>
+ <PARA>
+ You must have write access to the table in order to modify
+ it, as well as read access to any table whose values are
+ read in the <replaceable class="parameter">condition</replaceable>.
+ </PARA>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-DELETE-2">
+ <TITLE>
+ Usage
+ </TITLE>
+ <PARA>
+ Remove all films but musicals:
+ </PARA>
+ <ProgramListing>
+ DELETE FROM films WHERE kind <> 'Musical';
+
+ SELECT * FROM films;
+
+ code |title |did| date_prod|kind |len
+ -----+-------------------------+---+----------+----------+------
+ UA501|West Side Story |105|1961-01-03|Musical | 02:32
+ TC901|The King and I |109|1956-08-11|Musical | 02:13
+ WD101|Bed Knobs and Broomsticks|111| |Musical | 01:57
+ </ProgramListing>
+ <para>
+ Clear the table films:
+ </para>
+ <programlisting>
+ DELETE FROM films;
+
+ SELECT * FROM films;
+ code|title|did|date_prod|kind|len
+ ----+-----+---+---------+----+---
+ (0 rows)
+ </programlisting>
+ </REFSECT1>
+
+ <REFSECT1 ID="R1-SQL-DELETE-3">
+ <TITLE>
+ Compatibility
+ </TITLE>
+ <PARA>
+ </PARA>
+
+ <REFSECT2 ID="R2-SQL-DELETE-4">
+ <REFSECT2INFO>
+ <DATE>1998-04-15</DATE>
+ </REFSECT2INFO>
+ <TITLE>
+ SQL92
+ </TITLE>
+ <PARA>
+ SQL92 defines a different syntax for a positioned DELETE statement:
+ </PARA>
+
+ <synopsis>
+ DELETE FROM <replaceable class="parameter">table</replaceable> WHERE CURRENT OF <replaceable class="parameter">cursor</replaceable>
+ </synopsis>
+ <para>
+ where <replaceable class="parameter">cursor</replaceable> identifies an open cursor.</para>
+ </refsect2>
+ </refsect1>
+</REFENTRY>
+
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+sgml-parent-document:nil
+sgml-default-dtd-file:"../reference.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:"/usr/lib/sgml/catalog"
+sgml-local-ecat-files:nil
+End:
+-->
\ No newline at end of file
--- /dev/null
+<REFENTRY ID="SQL-RESET">
+<REFMETA>
+<REFENTRYTITLE>
+RESET
+</REFENTRYTITLE>
+<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+</REFMETA>
+<REFNAMEDIV>
+<REFNAME>
+RESET
+</REFNAME>
+<REFPURPOSE>
+Restores run-time parameters for session to default values
+</REFPURPOSE>
+
+<REFSYNOPSISDIV>
+<REFSYNOPSISDIVINFO>
+<DATE>1998-09-01</DATE>
+</REFSYNOPSISDIVINFO>
+<SYNOPSIS>
+RESET <REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE>
+</SYNOPSIS>
+
+<REFSECT2 ID="R2-SQL-RESET-1">
+<REFSECT2INFO>
+<DATE>1998-09-01</DATE>
+</REFSECT2INFO>
+<TITLE>
+Inputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+ Refer to the SET statement for more information on available
+ variables.
+</variablelist>
+
+</REFSECT2>
+
+<REFSECT2 ID="R2-SQL-RESET-2">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Outputs
+</TITLE>
+<PARA>
+</PARA>
+
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+RESET VARIABLE
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if successfully.
+
+</VARIABLELIST>
+
+</REFSECT2>
+</REFSYNOPSISDIV>
+
+<REFSECT1 ID="R1-SQL-RESET-1">
+<REFSECT1INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT1INFO>
+<TITLE>
+Description
+</TITLE>
+<PARA>
+ The RESET statement restores variables to the default values.
+Refer to the SET command for details on allowed values and defaults.
+RESET is an alternate form for
+<synopsis>
+<command>SET <replaceable class="parameter">variable</replaceable> = DEFAULT</command>
+</synopsis>
+
+<REFSECT2 ID="R2-SQL-RESET-3">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Notes
+</TITLE>
+<PARA>
+The RESET statement is a <productname>Postgres</productname> language extension.
+<para>
+ Refer to SET/SHOW statements to set/show variable values.
+
+</REFSECT2>
+</refsect1>
+
+<REFSECT1 ID="R1-SQL-RESET-2">
+<TITLE>
+Usage
+</TITLE>
+<PARA>
+<ProgramListing>
+ -- reset DateStyle to its default;
+ RESET DateStyle;
+</programlisting>
+<programlisting>
+ -- reset Geqo to its default;
+ RESET GEQO;
+</ProgramListing>
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-RESET-3">
+<TITLE>
+Compatibility
+</TITLE>
+<PARA>
+</PARA>
+
+<REFSECT2 ID="R2-SQL-RESET-4">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+SQL92
+</TITLE>
+<PARA>
+ There is no RESET statement in SQL92.
+</REFENTRY>
+
+<!--
+<REPLACEABLE CLASS="PARAMETER">
+</REPLACEABLE>
+<ReturnValue></ReturnValue>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>•
+</TERM>
+<LISTITEM>
+<PARA>
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+<PARA>
+</PARA>
+-->
--- /dev/null
+<REFENTRY ID="SQL-REVOKE">
+<REFMETA>
+<REFENTRYTITLE>
+REVOKE
+</REFENTRYTITLE>
+<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+</REFMETA>
+<REFNAMEDIV>
+<REFNAME>
+REVOKE
+</REFNAME>
+<REFPURPOSE>
+Revokes access privilege from a user, a group or all users.
+</REFPURPOSE>
+
+<REFSYNOPSISDIV>
+<REFSYNOPSISDIVINFO>
+<DATE>1998-09-01</DATE>
+</REFSYNOPSISDIVINFO>
+<SYNOPSIS>
+<REPLACEABLE CLASS="PARAMETER">
+</REPLACEABLE>
+REVOKE <REPLACEABLE CLASS="PARAMETER">privilege</REPLACEABLE> [, ...]
+ ON <REPLACEABLE CLASS="PARAMETER">object</REPLACEABLE> [, ...]
+ FROM { PUBLIC | GROUP <REPLACEABLE CLASS="PARAMETER">group</REPLACEABLE> | <REPLACEABLE CLASS="PARAMETER">username</REPLACEABLE> }
+</SYNOPSIS>
+
+<REFSECT2 ID="R2-SQL-REVOKE-1">
+<REFSECT2INFO>
+<DATE>1998-09-01</DATE>
+</REFSECT2INFO>
+<TITLE>
+Inputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">privilege</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+ The possible privileges are:
+
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+SELECT
+</TERM>
+<LISTITEM>
+<PARA>
+Privilege to access all of the columns of a specific
+ table/view.
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+
+<VARLISTENTRY>
+<TERM>
+INSERT
+</TERM>
+<LISTITEM>
+<PARA>
+Privilege to insert data into all columns of a
+ specific table.
+
+<VARLISTENTRY>
+<TERM>
+UPDATE
+</TERM>
+<LISTITEM>
+<PARA>
+Privilege to update all columns of a specific
+ table.
+
+<VARLISTENTRY>
+<TERM>
+DELETE
+</TERM>
+<LISTITEM>
+<PARA>
+Privilege to delete rows from a specific table.
+
+<VARLISTENTRY>
+<TERM>
+RULE
+</TERM>
+<LISTITEM>
+<PARA>
+Privilege to define rules on table/view.
+(See the <command>CREATE RULE</command> statement).
+
+<VARLISTENTRY>
+<TERM>
+ALL
+</TERM>
+<LISTITEM>
+<PARA>
+Rescind all privileges.
+
+</VARIABLELIST>
+
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">object</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+The name of an object from which to revoke access.
+ The possible objects are:
+<simplelist>
+<member>
+ table
+<member>
+ view
+<member>
+ sequence
+<member>
+ index
+</simplelist>
+
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">group</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+ The name of a group from whom to revoke privileges.
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">username</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+The name of a user from whom revoke privileges. Use the PUBLIC keyword
+to specify all users.
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+
+<VARLISTENTRY>
+<TERM>
+PUBLIC
+</TERM>
+<LISTITEM>
+<PARA>
+Rescind the specified privilege(s) for all users.
+
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+
+</REFSECT2>
+
+<REFSECT2 ID="R2-SQL-REVOKE-2">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Outputs
+</TITLE>
+<PARA>
+</PARA>
+
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+CHANGE
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if successfully.
+
+<VARLISTENTRY>
+<TERM>
+ERROR
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if object is not available or impossible
+ to revoke privileges from a group or users.
+
+</VARIABLELIST>
+
+</REFSECT2>
+</REFSYNOPSISDIV>
+
+<REFSECT1 ID="R1-SQL-REVOKE-1">
+<REFSECT1INFO>
+<DATE>1998-09-01</DATE>
+</REFSECT1INFO>
+<TITLE>
+Description
+</TITLE>
+<PARA>
+ REVOKE allows creator of an object to revoke permissions granted
+ before, from all users (via PUBLIC) or a certain user or group.
+
+<REFSECT2 ID="R2-SQL-REVOKE-3">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Notes
+</TITLE>
+<PARA>
+ Refer to psql \z command for further information about permissions
+ on existing objects:
+
+<programlisting>
+ Database = lusitania
+ +------------------+---------------------------------------------+
+ | Relation | Grant/Revoke Permissions |
+ +------------------+---------------------------------------------+
+ | mytable | {"=rw","miriam=arwR","group todos=rw"} |
+ +------------------+---------------------------------------------+
+ Legend:
+ uname=arwR -- privileges granted to a user
+ group gname=arwR -- privileges granted to a GROUP
+ =arwR -- privileges granted to PUBLIC
+
+ r -- SELECT
+ w -- UPDATE/DELETE
+ a -- INSERT
+ R -- RULE
+ arwR -- ALL
+</programlisting>
+
+<tip>
+<para>
+Currently, to create a GROUP you have to insert
+ data manually into table pg_group as:
+<programlisting>
+ INSERT INTO pg_group VALUES ('todos');
+ CREATE USER miriam IN GROUP todos;
+</programlisting>
+</tip>
+
+</REFSECT2>
+
+<REFSECT1 ID="R1-SQL-REVOKE-2">
+<TITLE>
+Usage
+</TITLE>
+<PARA>
+<ProgramListing>
+ -- revoke insert privilege from all users on table films:
+ --
+ REVOKE INSERT ON films FROM PUBLIC;
+
+ -- revoke all privileges from user manuel on view kinds:
+ --
+ REVOKE ALL ON kinds FROM manuel;
+</ProgramListing>
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-REVOKE-3">
+<TITLE>
+Compatibility
+</TITLE>
+<PARA>
+</PARA>
+
+<REFSECT2 ID="R2-SQL-REVOKE-4">
+<REFSECT2INFO>
+<DATE>1998-09-01</DATE>
+</REFSECT2INFO>
+<TITLE>
+SQL92
+</TITLE>
+<PARA>
+ The SQL92 syntax for REVOKE has additional capabilities for rescinding
+privileges, including those on individual columns in tables:
+
+<variablelist>
+<varlistentry>
+<term>
+<synopsis>
+REVOKE { SELECT | DELETE | USAGE | ALL PRIVILEGES } [, ...]
+ ON <replaceable class="parameter">object</replaceable>
+ FROM { PUBLIC | <replaceable class="parameter">username</replaceable> [, ...] } { RESTRICT | CASCADE }
+REVOKE { INSERT | UPDATE | REFERENCES } [, ...] [ ( <replaceable class="parameter">column</replaceable> [, ...] ) ]
+ ON <replaceable class="parameter">object</replaceable>
+ FROM { PUBLIC | <replaceable class="parameter">username</replaceable> [, ...] } { RESTRICT | CASCADE }
+</synopsis>
+<listitem>
+<para>
+Refer to the <command>GRANT</command> command for details on individual fields.
+
+<varlistentry>
+<term>
+<synopsis>
+REVOKE GRANT OPTION FOR <replaceable class="parameter">privilege</replaceable> [, ...]
+ ON <replaceable class="parameter">object</replaceable>
+ FROM { PUBLIC | <replaceable class="parameter">username</replaceable> [, ...] } { RESTRICT | CASCADE }
+</synopsis>
+<listitem>
+<para>
+Rescinds authority for a user to grant the specified privilege to others.
+Refer to the <command>GRANT</command> command for details on individual fields.
+
+</variablelist>
+
+<para>
+ The possible objects are:
+<simplelist>
+<member> [ TABLE ] table/view
+<member> CHARACTER SET character-set
+<member> COLLATION collation
+<member> TRANSLATION translation
+<member> DOMAIN domain
+</simplelist>
+
+<para>
+If user1 gives a privilege WITH GRANT OPTION to user2,
+ and user2 gives it to user3 then user1 can revoke
+ this privilege in cascade using the CASCADE keyword.
+
+If user1 gives a privilege WITH GRANT OPTION to user2,
+ and user2 gives it to user3 then if user1 try revoke
+ this privilege it fails if he/she specify the RESTRICT
+ keyword.
+</REFENTRY>
+
+<!--
+<REPLACEABLE CLASS="PARAMETER">
+</REPLACEABLE>
+<ReturnValue></ReturnValue>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>•
+</TERM>
+<LISTITEM>
+<PARA>
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+<PARA>
+</PARA>
+-->
--- /dev/null
+<REFENTRY ID="SQL-ROLLBACK">
+<REFMETA>
+<REFENTRYTITLE>
+ROLLBACK
+</REFENTRYTITLE>
+<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+</REFMETA>
+<REFNAMEDIV>
+<REFNAME>
+ROLLBACK
+</REFNAME>
+<REFPURPOSE>
+Aborts the current transaction
+</REFPURPOSE>
+<REFSYNOPSISDIV>
+<REFSYNOPSISDIVINFO>
+<DATE>1998-09-01</DATE>
+</REFSYNOPSISDIVINFO>
+<SYNOPSIS>
+ROLLBACK [ WORK ]
+</SYNOPSIS>
+
+<REFSECT2 ID="R2-SQL-ROLLBACK-1">
+<REFSECT2INFO>
+<DATE>1998-09-01</DATE>
+</REFSECT2INFO>
+<TITLE>
+Inputs
+</TITLE>
+<PARA>
+None.
+
+</REFSECT2>
+
+<REFSECT2 ID="R2-SQL-ROLLBACK-2">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Outputs
+</TITLE>
+<PARA>
+
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+ ABORT
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if successful.
+
+<VARLISTENTRY>
+<TERM>
+NOTICE: UserAbortTransactionBlock and not in in-progress state
+ABORT
+</TERM>
+<LISTITEM>
+<PARA>
+ If there is not any transaction currently in progress.
+
+</VARLISTENTRY>
+</VARIABLELIST>
+
+</REFSECT2>
+</REFSYNOPSISDIV>
+
+<REFSECT1 ID="R1-SQL-ROLLBACK-1">
+<REFSECT1INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT1INFO>
+<TITLE>
+Description
+</TITLE>
+<PARA>
+ ROLLBACK rolls back the current transaction and causes
+ all the updates made by the transaction to be discarded.
+
+<REFSECT2 ID="R2-SQL-ROLLBACK-3">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Notes
+</TITLE>
+<PARA>
+The keyword WORK is noise and can be omitted.
+
+<para>
+Use the COMMIT statement to successfully terminate a transaction.
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-ROLLBACK-2">
+<TITLE>
+Usage
+</TITLE>
+<PARA>
+<ProgramListing>
+ --To abort all changes:
+ --
+ ROLLBACK WORK;
+</ProgramListing>
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-ROLLBACK-3">
+<TITLE>
+Compatibility
+</TITLE>
+<PARA>
+</PARA>
+
+<REFSECT2 ID="R2-SQL-ROLLBACK-4">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+SQL92
+</TITLE>
+<PARA>
+ Full compatibility.
+</REFENTRY>
+
+<!--
+<REPLACEABLE CLASS="PARAMETER">
+</REPLACEABLE>
+<ReturnValue></ReturnValue>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>•
+</TERM>
+<LISTITEM>
+<PARA>
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+<PARA>
+</PARA>
+-->
Description
</TITLE>
<PARA>
+SELECT is the principal means to access information
+ in <productname>Postgres</productname>.
+
SELECT will get all rows which satisfy the WHERE condition
or all rows of a table if WHERE is omitted.
The GROUP BY clause allows a user to divide a table
conceptually into groups. (See GROUP BY clause).
-<PARA>
The HAVING clause specifies a grouped table derived by the
elimination of groups from the result of the previously
specified clause. (See HAVING clause).
-<PARA>
The ORDER BY clause allows a user to specify that he/she
wishes the rows sorted according to the ASCending or
DESCending mode operator. (See ORDER BY clause)
-<PARA>
The UNION clause specifies a table derived from a Cartesian
product union join. (See UNION clause).
--- /dev/null
+<REFENTRY ID="SQL-SET">
+<REFMETA>
+<REFENTRYTITLE>
+SET
+</REFENTRYTITLE>
+<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+</REFMETA>
+<REFNAMEDIV>
+<REFNAME>
+SET
+</REFNAME>
+<REFPURPOSE>
+ Set run-time parameters for session
+</REFPURPOSE>
+<REFSYNOPSISDIV>
+<REFSYNOPSISDIVINFO>
+<DATE>1998-08-31</DATE>
+</REFSYNOPSISDIVINFO>
+<SYNOPSIS>
+<REPLACEABLE CLASS="PARAMETER">
+</REPLACEABLE>
+SET <REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE> { TO | = } { '<REPLACEABLE CLASS="PARAMETER">value</REPLACEABLE>' | DEFAULT }
+
+SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL };
+</SYNOPSIS>
+
+<REFSECT2 ID="R2-SQL-SET-1">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+Inputs
+</TITLE>
+<PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<para>
+Settable global parameter.
+
+<varlistentry>
+<term>
+<REPLACEABLE CLASS="PARAMETER">value</REPLACEABLE>
+</term>
+<listitem>
+<PARA>
+New value of parameter.
+</variablelist>
+
+<para>
+ The possible variables and allowed values are:
+
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+DateStyle
+</TERM>
+<LISTITEM>
+<PARA>
+
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+ISO
+</TERM>
+<LISTITEM>
+<PARA>
+use ISO 8601-style dates and times
+<VARLISTENTRY>
+<TERM>
+SQL
+</TERM>
+<LISTITEM>
+<PARA>
+use Oracle/Ingres-style dates and times
+<VARLISTENTRY>
+<TERM>
+Postgres
+</TERM>
+<LISTITEM>
+<PARA>
+use traditional <productname>Postgres</productname> format
+<VARLISTENTRY>
+<TERM>
+European
+</TERM>
+<LISTITEM>
+<PARA>
+use dd/mm/yyyy for numeric date representations.
+<VARLISTENTRY>
+<TERM>
+NonEuropean
+</TERM>
+<LISTITEM>
+<PARA>
+use mm/dd/yyyy for numeric date representations.
+<VARLISTENTRY>
+<TERM>
+German
+</TERM>
+<LISTITEM>
+<PARA>
+use dd.mm.yyyy for numeric date representations.
+<VARLISTENTRY>
+<TERM>
+US
+</TERM>
+<LISTITEM>
+<PARA>
+same as 'NonEuropean'
+<VARLISTENTRY>
+<TERM>
+default
+</TERM>
+<LISTITEM>
+<PARA>
+restores the default values ('US,Postgres')
+</varlistentry>
+</variablelist>
+
+<para>
+ Date format initialization my be done by:
+<simplelist>
+<member>
+Setting PGDATESTYLE environment variable.
+
+<member>
+Running postmaster using -oe parameter to set
+ dates to the 'European' convention.
+Note that this affects only the some combinations of date styles; for example
+the ISO style is not affected by this parameter.
+<member>
+Changing variables in
+<filename>src/backend/utils/init/globals.c</filename>.
+</simplelist>
+
+<para>
+The variables in <filename>globals.c</filename> which can be changed are:
+<programlisting>
+bool EuroDates = false
+ true
+int DateStyle = USE_ISO_DATES
+ USE_POSTGRES_DATES
+ USE_ISO_DATES
+ USE_SQL_DATES
+ USE_GERMAN_DATES
+</programlisting>
+
+</varlistentry>
+
+<varlistentry>
+<term>
+TIMEZONE
+</term>
+<listitem>
+<para>
+ The possible values for timezone depends on your operating
+ system. For example on Linux /usr/lib/zoneinfo contains the
+ database of timezones.
+<para>
+ Here are some valid values for timezone:
+
+<variablelist>
+<varlistentry>
+<term>
+'PST8PDT'
+</term>
+<listitem>
+<para>
+set the timezone for California
+<varlistentry>
+<term>
+'Portugal'
+</term>
+<listitem>
+<para>
+set time zone for Portugal.
+<varlistentry>
+<term>
+'Europe/Rome'
+</term>
+<listitem>
+<para>
+set time zone for Italy.
+<varlistentry>
+<term>
+DEFAULT
+</term>
+<listitem>
+<para>
+set time zone to your local timezone
+(value of the TZ environment variable).
+</variablelist>
+
+<para>
+ If an invalid time zone is specified, the time zone
+ becomes GMT (on most systems anyway).
+<para>
+ A frontend which uses libpq may be initialized by setting the PGTZ
+ environment variable.
+<para>
+ The second syntax shown above, allows one to set the timezone
+ with a syntax similar to SQL92 <command>SET TIME ZONE</command>.
+ The LOCAL keyword is just an alternate form
+ of DEFAULT for SQL92 compatibility.
+
+</varlistentry>
+</variablelist>
+
+There are also several internal or optimization parameters which can be specified
+by the <command>SET</command> command:
+
+<variablelist>
+<varlistentry>
+<term>
+COST_HEAP
+</term>
+<listitem>
+<para>
+Sets the default cost of a heap scan for use by the optimizer.
+
+<variablelist>
+<varlistentry>
+<term>
+<replaceable class="parameter">float4</replaceable>
+</term>
+<listitem>
+<para>
+Set the cost of a heap scan to the specified floating point value.
+
+<varlistentry>
+<term>
+DEFAULT
+</term>
+<listitem>
+<para>
+Sets the cost of a heap scan to the default value.
+</variablelist>
+
+<para>
+ The frontend may be initialized by setting the PGCOSTHEAP
+ environment variable.
+
+<varlistentry>
+<term>
+COST_INDEX
+</term>
+<listitem>
+<para>
+Sets the default cost of an index scan for use by the optimizer.
+
+<variablelist>
+<varlistentry>
+<term>
+<replaceable class="parameter">float4</replaceable>
+</term>
+<listitem>
+<para>
+Set the cost of an index scan to the specified floating point value.
+
+<varlistentry>
+<term>
+DEFAULT
+</term>
+<listitem>
+<para>
+Sets the cost of an index scan to the default value.
+</variablelist>
+
+<para>
+ The frontend may be initialized by setting the PGCOSTINDEX
+ environment variable.
+
+<varlistentry>
+<term>
+GEQO
+</term>
+<listitem>
+<para>
+Sets the threshold for using the genetic optimizer algorithm.
+
+<variablelist>
+<varlistentry>
+<term>
+On
+</term>
+<listitem>
+<para>
+enables the genetic optimizer algorithm
+ for statements with 8 or more tables.
+<varlistentry>
+<term>
+On=#
+</term>
+<listitem>
+<para>
+enables the genetic optimizer algorithm
+ for statements with # or more tables.
+<varlistentry>
+<term>
+Off
+</term>
+<listitem>
+<para>
+disables the genetic optimizer algorithm.
+<varlistentry>
+<term>
+DEFAULT
+</term>
+<listitem>
+<para>
+Equivalent to specifying <command>SET GEQO=On</command>
+</varlistentry>
+</variablelist>
+
+<para>
+ This algorithm is on by default, which used GEQO for
+ statements of eight or more tables.
+ (See the chapter on GEQO in the Programmer's Guide
+for more information).
+
+<para>
+ The frontend may be initialized by setting PGGEQO
+ environment variable.
+</varlistentry>
+
+<varlistentry>
+<term>
+R_PLANS
+</term>
+<listitem>
+<para>
+Determines whether right-hand plan evaluation is allowed:
+
+<variablelist>
+<varlistentry>
+<term>
+On
+</term>
+<listitem>
+<para>
+enables right-hand evaluation of plans.
+
+<varlistentry>
+<term>
+Off
+</term>
+<listitem>
+<para>
+disables right-hand evaluation of plans.
+
+<varlistentry>
+<term>
+DEFAULT
+</term>
+<listitem>
+<para>
+Equivalent to specifying <command>SET R_PLANS=Off</command>.
+</variablelist>
+
+<para>
+ It may be useful when joining big relations with
+ small ones. This algorithm is off by default.
+ It's not used by GEQO anyway.
+<para>
+ The frontend may be initialized by setting the PGRPLANS
+ environment variable.
+</varlistentry>
+
+<varlistentry>
+<term>
+R_PLANS
+</term>
+<listitem>
+<para>
+Determines whether right-hand plan evaluation is allowed:
+
+<variablelist>
+<varlistentry>
+<term>
+On
+</term>
+<listitem>
+<para>
+enables right-hand evaluation of plans.
+
+<varlistentry>
+<term>
+Off
+</term>
+<listitem>
+<para>
+disables right-hand evaluation of plans.
+
+<varlistentry>
+<term>
+DEFAULT
+</term>
+<listitem>
+<para>
+Equivalent to specifying <command>SET R_PLANS=Off</command>.
+</variablelist>
+
+<para>
+ It may be useful when joining big relations with
+ small ones. This algorithm is off by default.
+ It's not used by GEQO anyway.
+<para>
+ The frontend may be initialized by setting the PGRPLANS
+ environment variable.
+
+</VARLISTENTRY>
+</VARIABLELIST>
+</REFSECT2>
+
+<REFSECT2 ID="R2-SQL-SET-2">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+Outputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+ SET VARIABLE
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if successfully.
+
+<VARLISTENTRY>
+<TERM>
+ WARN: Bad value for <replaceable class="parameter">variable</replaceable> (<replaceable class="parameter">value</replaceable>)
+</TERM>
+<LISTITEM>
+<PARA>
+ If fails to set variable.
+</VARLISTENTRY>
+</VARIABLELIST>
+
+</REFSECT2>
+</REFSYNOPSISDIV>
+
+<REFSECT1 ID="R1-SQL-SET-1">
+<REFSECT1INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT1INFO>
+<TITLE>
+Description
+</TITLE>
+<PARA>
+SET will modify configuration parameters for variable during
+ a session.
+
+<para>
+ Current values can be obtained using SHOW statement, and values
+ can be restored to the defaults using RESET statement.
+ Parameters and values are case-insensitive. Note that the value
+ field is always specified as a string, so is enclosed in
+ single-quotes.
+<para>
+ SET TIME ZONE changes the session's default time zone offset.
+ A SQL-session always begins with an initial default time zone
+ offset.
+ The SET TIME ZONE statement is used to change the default
+ time zone offset for the current SQL session.
+
+<REFSECT2 ID="R2-SQL-SET-3">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+Notes
+</TITLE>
+<PARA>
+The <command>SET <replaceable class="parameter">variable</replaceable></command>
+ statement is a <productname>Postgres</productname> language extension.
+
+<para>
+ Refer to SHOW/RESET statements to show/reset variable values.
+
+</REFSECT2>
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-SET-2">
+<TITLE>
+Usage
+</TITLE>
+<PARA>
+</PARA>
+<ProgramListing>
+ --Set the style of date to ISO:
+ --
+ SET DATESTYLE TO 'ISO';
+</programlisting>
+<programlisting>
+ --Set GEQO to default:
+ --
+ SET GEQO = DEFAULT;
+</programlisting>
+<programlisting>
+ --Turn on right-hand evaluation of plans:
+ --
+ SET R_PLANS TO 'on';
+</programlisting>
+<programlisting>
+ --set the timezone for Berkeley, California:
+ SET TIME ZONE 'PST8PDT';
+
+ SELECT CURRENT_TIMESTAMP AS today;
+
+ today
+ ----------------------
+ 1998-03-31 07:41:21-08
+</programlisting>
+<programlisting>
+ --set the timezone for Italy:
+ SET TIME ZONE 'Europe/Rome';
+
+ SELECT CURRENT_TIMESTAMP AS today;
+
+ today
+ ----------------------
+ 1998-03-31 17:41:31+02
+</ProgramListing>
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-SET-3">
+<TITLE>
+Compatibility
+</TITLE>
+<PARA>
+</PARA>
+
+<REFSECT2 ID="R2-SQL-SET-4">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+SQL92
+</TITLE>
+<PARA>
+ There is no
+<command>SET <replaceable class="parameter">variable</replaceable></command>
+ in SQL92.
+
+ The SQL92 syntax for SET TIME ZONE is slightly different,
+ allowing only a single integer value for time zone specification:
+
+<programlisting>
+SET TIME ZONE { interval_value_expression | LOCAL }
+</programlisting>
+
+</REFENTRY>
+
+<!--
+<REPLACEABLE CLASS="PARAMETER">
+</REPLACEABLE>
+<ReturnValue></ReturnValue>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>•
+</TERM>
+<LISTITEM>
+<PARA>
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+<PARA>
+</PARA>
+-->
--- /dev/null
+<REFENTRY ID="SQL-SHOW">
+<REFMETA>
+<REFENTRYTITLE>
+SHOW
+</REFENTRYTITLE>
+<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+</REFMETA>
+<REFNAMEDIV>
+<REFNAME>
+SHOW
+</REFNAME>
+<REFPURPOSE>
+Shows run-time parameters for session
+</REFPURPOSE>
+<REFSYNOPSISDIV>
+<REFSYNOPSISDIVINFO>
+<DATE>1998-08-31</DATE>
+</REFSYNOPSISDIVINFO>
+<SYNOPSIS>
+SHOW <REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE>
+</SYNOPSIS>
+
+<REFSECT2 ID="R2-SQL-SHOW-1">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+Inputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+ Refer to the SET statement for more information on available
+ variables.
+</VARLISTENTRY>
+</VARIABLELIST>
+
+</REFSECT2>
+
+<REFSECT2 ID="R2-SQL-SHOW-2">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+Outputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+NOTICE: <REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE> is <ReturnValue>value</ReturnValue>
+SHOW VARIABLE
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if successfully.
+</listitem>
+<VARLISTENTRY>
+<TERM>
+NOTICE: Unrecognized variable <ReturnValue>value</ReturnValue>
+<LISTITEM>
+<PARA>
+Message returned if <ReturnValue>value</ReturnValue> does not exist.
+</PARA>
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+</REFSECT2>
+</REFSYNOPSISDIV>
+
+<REFSECT1 ID="R1-SQL-SHOW-1">
+<REFSECT1INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT1INFO>
+<TITLE>
+Description
+</TITLE>
+<PARA>
+ SHOW will display the current configuration parameters for
+ variable during a session.
+
+<para>
+ The session can be configured using SET statement, and values
+ can be restored to the defaults using RESET statement.
+ Parameters and values are case-insensitive.
+
+<REFSECT2 ID="R2-SQL-SHOW-3">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+Notes
+</TITLE>
+<PARA>
+ The SHOW statement is a <productname>Postgres</productname>
+ language extension.
+
+<para>
+ Refer to the SET/RESET statements to set/reset variable values.
+ See also the SET TIME ZONE statement.
+
+<para>
+ If the TZ environment variable is not set the SHOW TIME ZONE statement
+ gives the message: Time zone is unknown
+</REFSECT2>
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-SHOW-2">
+<TITLE>
+Usage
+</TITLE>
+<PARA>
+<ProgramListing>
+ -- show DateStyle;
+ SHOW DateStyle;
+ NOTICE:DateStyle is Postgres with US (NonEuropean) conventions
+
+ -- show Geqo;
+ SHOW GEQO;
+ NOTICE:GEQO is ON
+</ProgramListing>
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-SHOW-3">
+<TITLE>
+Compatibility
+</TITLE>
+<PARA>
+</PARA>
+
+<REFSECT2 ID="R2-SQL-SHOW-4">
+<REFSECT2INFO>
+<DATE>1998-08-31</DATE>
+</REFSECT2INFO>
+<TITLE>
+SQL92
+</TITLE>
+<PARA>
+ There is no SET statement defined in <acronym>SQL92</acronym>.
+</refsect2>
+</refsect1>
+</REFENTRY>
--- /dev/null
+<REFENTRY ID="SQL-UPDATE">
+<REFMETA>
+<REFENTRYTITLE>
+UPDATE
+</REFENTRYTITLE>
+<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
+</REFMETA>
+<REFNAMEDIV>
+<REFNAME>
+UPDATE
+</REFNAME>
+<REFPURPOSE>
+Replaces values of columns in a table
+</REFPURPOSE>
+
+<REFSYNOPSISDIV>
+<REFSYNOPSISDIVINFO>
+<DATE>1998-04-15</DATE>
+</REFSYNOPSISDIVINFO>
+<SYNOPSIS>
+UPDATE <REPLACEABLE CLASS="PARAMETER">table</replaceable> SET <REPLACEABLE CLASS="PARAMETER">column</replaceable> = <REPLACEABLE CLASS="PARAMETER">expression</replaceable> [, ...]
+ [FROM <REPLACEABLE CLASS="PARAMETER">fromlist</REPLACEABLE>]
+ [WHERE <REPLACEABLE CLASS="PARAMETER">condition</REPLACEABLE>]
+</SYNOPSIS>
+
+<REFSECT2 ID="R2-SQL-UPDATE-1">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Inputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">table</replaceable>
+</TERM>
+<LISTITEM>
+<PARA>
+ The name of an existing table.
+</LISTITEM>
+</VARLISTENTRY>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">column</replaceable>
+</TERM>
+<LISTITEM>
+<PARA>
+The name of a column in <REPLACEABLE CLASS="PARAMETER">table</replaceable>.
+</LISTITEM>
+</VARLISTENTRY>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">expression</replaceable>
+</TERM>
+<LISTITEM>
+<PARA>
+ A valid expression or value to assign to column.
+</LISTITEM>
+</VARLISTENTRY>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">fromlist</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+ A <productname>Postgres</productname>
+ non-standard extension to allow columns
+ from other tables to appear in the WHERE condition.
+</LISTITEM>
+</VARLISTENTRY>
+<VARLISTENTRY>
+<TERM>
+<REPLACEABLE CLASS="PARAMETER">condition</REPLACEABLE>
+</TERM>
+<LISTITEM>
+<PARA>
+ Refer to the SELECT statement for a further description
+ of the WHERE clause.
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+</REFSECT2>
+
+<REFSECT2 ID="R2-SQL-UPDATE-2">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+Outputs
+</TITLE>
+<PARA>
+</PARA>
+<VARIABLELIST>
+<VARLISTENTRY>
+<TERM>
+UPDATE <replaceable class="parameter">#</replaceable>
+</TERM>
+<LISTITEM>
+<PARA>
+ Message returned if successful.
+The <replaceable class="parameter">#</replaceable>
+ means the number of rows updated.
+If <replaceable class="parameter">#</replaceable>
+ is equal 0 no rows are updated.
+</LISTITEM>
+</VARLISTENTRY>
+</VARIABLELIST>
+
+</REFSECT2>
+</REFSYNOPSISDIV>
+
+<REFSECT1 ID="R1-SQL-UPDATE-1">
+<REFSECT1INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT1INFO>
+<TITLE>
+Description
+</TITLE>
+<PARA>
+ UPDATE changes the values of the columns specified for
+ all rows which satisfy condition. Only the columns
+ to be modified need appear as column.
+
+<PARA>
+ Array references use the same syntax found in SELECT.
+ That is, either single array elements, a range of array
+ elements or the entire array may be replaced with a single
+ query.
+
+<PARA>
+ You must have write access to the table in order to modify
+ it, as well as read access to any table whose values are
+ mentioned in the WHERE condition.
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-UPDATE-2">
+<TITLE>
+Usage
+</TITLE>
+<PARA>
+</PARA>
+<ProgramListing>
+ --Change word "Drama" with "Dramatic" on column kind:
+ --
+ UPDATE films
+ SET kind = 'Dramatic'
+ WHERE kind = 'Drama';
+
+ SELECT * FROM films WHERE kind = 'Dramatic' OR kind = 'Drama';
+
+ code |title |did| date_prod|kind |len
+ -----+-------------+---+----------+----------+------
+ BL101|The Third Man|101|1949-12-23|Dramatic | 01:44
+ P_302|Becket |103|1964-02-03|Dramatic | 02:28
+ M_401|War and Peace|104|1967-02-12|Dramatic | 05:57
+ T_601|Yojimbo |106|1961-06-16|Dramatic | 01:50
+ DA101|Das Boot |110|1981-11-11|Dramatic | 02:29
+</ProgramListing>
+
+</REFSECT1>
+
+<REFSECT1 ID="R1-SQL-UPDATE-3">
+<TITLE>
+Compatibility
+</TITLE>
+<PARA>
+</PARA>
+
+<REFSECT2 ID="R2-SQL-UPDATE-4">
+<REFSECT2INFO>
+<DATE>1998-04-15</DATE>
+</REFSECT2INFO>
+<TITLE>
+SQL92
+</TITLE>
+<PARA>
+ SQL92 defines a different syntax for positioned UPDATE statement:
+
+<programlisting>
+ UPDATE table SET column = expression [, ...]
+ WHERE CURRENT OF <replaceable class="parameter">cursor</replaceable>
+</programlisting>
+
+ where <replaceable class="parameter">cursor</replaceable>
+ identifies an open cursor.
+</REFENTRY>
projects / postgresql / commitdiff