Correct/improve the datetime_precision field in the information schema.

[postgresql] / doc / src / sgml / information_schema.sgml

diff --git a/doc/src/sgml/information_schema.sgml b/doc/src/sgml/information_schema.sgml
index 06ccb6d2deaa3be898985626db04b15ca208b140..b6e143c5da54bc9e8965313ebb414910ac9bb150 100644 (file)
--- a/doc/src/sgml/information_schema.sgml
+++ b/doc/src/sgml/information_schema.sgml
@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/information_schema.sgml,v 1.38 2009/02/06 21:15:11 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/information_schema.sgml,v 1.39 2009/06/10 07:03:34 petere Exp $ -->
 
 <chapter id="information-schema">
  <title>The Information Schema</title>
@@ -395,9 +395,12 @@
       <entry><literal>datetime_precision</literal></entry>
       <entry><type>cardinal_number</type></entry>
       <entry>
-       If <literal>data_type</literal> identifies a date, time, or
-       interval type, the declared precision; null for all other data
-       types or if no precision was declared.
+       If <literal>data_type</literal> identifies a date, time,
+       timestamp, or interval type, this column contains the (declared
+       or implicit) fractional seconds precision of the type for this
+       attribute, that is, the number of decimal digits maintained
+       following the decimal point in the seconds value.  For all
+       other data types, this column is null.
       </entry>
      </row>
 
@@ -995,9 +998,12 @@
       <entry><literal>datetime_precision</literal></entry>
       <entry><type>cardinal_number</type></entry>
       <entry>
-       If <literal>data_type</literal> identifies a date, time, or
-       interval type, the declared precision; null for all other data
-       types or if no precision was declared.
+       If <literal>data_type</literal> identifies a date, time,
+       timestamp, or interval type, this column contains the (declared
+       or implicit) fractional seconds precision of the type for this
+       column, that is, the number of decimal digits maintained
+       following the decimal point in the seconds value.  For all
+       other data types, this column is null.
       </entry>
      </row>
 
@@ -1729,7 +1735,7 @@
       <entry><type>cardinal_number</type></entry>
       <entry>
        If the domain has a numeric type, this column contains the
-       (declared or implicit) precision of the type for this column.
+       (declared or implicit) precision of the type for this domain.
        The precision indicates the number of significant digits.  It
        can be expressed in decimal (base 10) or binary (base 2) terms,
        as specified in the column
@@ -1755,7 +1761,7 @@
       <entry><type>cardinal_number</type></entry>
       <entry>
        If the domain has an exact numeric type, this column contains
-       the (declared or implicit) scale of the type for this column.
+       the (declared or implicit) scale of the type for this domain.
        The scale indicates the number of significant digits to the
        right of the decimal point.  It can be expressed in decimal
        (base 10) or binary (base 2) terms, as specified in the column
@@ -1768,9 +1774,12 @@
       <entry><literal>datetime_precision</literal></entry>
       <entry><type>cardinal_number</type></entry>
       <entry>
-       If the domain has a date, time, or interval type, the declared
-       precision; null for all other data types or if no precision was
-       declared.
+       If <literal>data_type</literal> identifies a date, time,
+       timestamp, or interval type, this column contains the (declared
+       or implicit) fractional seconds precision of the type for this
+       domain, that is, the number of decimal digits maintained
+       following the decimal point in the seconds value.  For all
+       other data types, this column is null.
       </entry>
      </row>