From ec27da1ce31ccdd1f62df75a4b1e796b6d66fa9c Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 23 Nov 2001 21:08:51 +0000 Subject: [PATCH] Copy-editing. --- doc/src/sgml/advanced.sgml | 4 ++-- doc/src/sgml/query.sgml | 29 ++++++++++++++++++----------- doc/src/sgml/start.sgml | 8 ++++---- 3 files changed, 24 insertions(+), 17 deletions(-) diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml index 96b2226f93..36721068f9 100644 --- a/doc/src/sgml/advanced.sgml +++ b/doc/src/sgml/advanced.sgml @@ -1,5 +1,5 @@ @@ -132,7 +132,7 @@ ERROR: <unnamed> referential integrity violation - key referenced from we The behavior of foreign keys can be finely tuned to your application. We will not go beyond this simple example in this - tutorial and refer you to the Reference + tutorial, but just refer you to the Reference Manual for more information. Making correct use of foreign keys will definitely improve the quality of your database applications, so you are strongly encouraged to learn about them. diff --git a/doc/src/sgml/query.sgml b/doc/src/sgml/query.sgml index 7dd39de589..6f1f20f9d7 100644 --- a/doc/src/sgml/query.sgml +++ b/doc/src/sgml/query.sgml @@ -1,5 +1,5 @@ @@ -15,8 +15,8 @@ $Header: /cvsroot/pgsql/doc/src/sgml/query.sgml,v 1.21 2001/11/19 05:37:53 tgl E way a complete tutorial on SQL. Numerous books have been written on SQL92, including and . - You should be aware that some language - features are extensions to the standard. + You should be aware that some PostgreSQL + language features are extensions to the standard. @@ -44,7 +44,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/query.sgml,v 1.21 2001/11/19 05:37:53 tgl E The \i command reads in commands from the specified file. The -s option puts you in - single step mode which pauses before sending a query to the + single step mode which pauses before sending each query to the server. The commands used in this section are in the file basics.sql. @@ -78,11 +78,12 @@ $Header: /cvsroot/pgsql/doc/src/sgml/query.sgml,v 1.21 2001/11/19 05:37:53 tgl E column Each table is a named collection of rows. - Each row has the same set of named columns, + Each row of a given table has the same set of named + columns, and each column is of a specific data type. Whereas columns have a fixed order in each row, it is important to remember that SQL does not guarantee the order of the rows within the table in any - way (unless they are explicitly sorted). + way (although they can be explicitly sorted for display). @@ -200,7 +201,10 @@ DROP TABLE tablename; INSERT INTO weather VALUES ('San Francisco', 46, 50, 0.25, '1994-11-27'); - Note that all data types use rather obvious input formats. The + Note that all data types use rather obvious input formats. + Constants that are not simple numeric values usually must be + surrounded by single quotes ('), as in the example. + The date column is actually quite flexible in what it accepts, but for this tutorial we will stick to the unambiguous format shown here. @@ -223,7 +227,7 @@ INSERT INTO weather (city, temp_lo, temp_hi, prcp, date) VALUES ('San Francisco', 43, 57, 0.0, '1994-11-29'); You can list the columns in a different order if you wish or - even omit some columns, e.g., unknown precipitation: + even omit some columns, e.g., if the precipitation is unknown: INSERT INTO weather (date, city, temp_hi, temp_lo) VALUES ('1994-11-29', 'Hayward', 54, 37); @@ -654,7 +658,9 @@ SELECT city, max(temp_lo) (2 rows) - which gives us one output row per city. We can filter these grouped + which gives us one output row per city. Each aggregate result is + computed over the table rows matching that city. + We can filter these grouped rows using HAVING: @@ -671,8 +677,9 @@ SELECT city, max(temp_lo) (1 row) - which gives us the same results for only the cities that have some - below-forty readings. Finally, if we only care about cities whose + which gives us the same results for only the cities that have all + temp_lo values below forty. Finally, if we only care about + cities whose names begin with S, we might do diff --git a/doc/src/sgml/start.sgml b/doc/src/sgml/start.sgml index bda58c4ef1..e94764033c 100644 --- a/doc/src/sgml/start.sgml +++ b/doc/src/sgml/start.sgml @@ -1,5 +1,5 @@ @@ -160,7 +160,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/start.sgml,v 1.19 2001/11/21 06:09:45 thoma CREATE DATABASE - Is so, this step was successful and you can skip over the + If so, this step was successful and you can skip over the remainder of this section. @@ -173,7 +173,7 @@ createdb: command not found installed at all or the search path was not set correctly. Try calling the command with an absolute path instead: -$ /usr/local/pgsql/bin/createdb +$ /usr/local/pgsql/bin/createdb mydb The path at your site might be different. Contact your site administrator or check back in the installation instructions to @@ -249,7 +249,7 @@ createdb: database creation failed $ dropdb mydb - (In this case, the database name does not default to the user + (For this command, the database name does not default to the user account name. You always need to specify it.) This action physically removes all files associated with the database and cannot be undone, so this should only be done with a great deal of -- 2.49.0