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Add a few more cross-references where appropriate, add more text about

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the FROM clause and an example to the UPDATE reference page, and make
a few other SGML tweaks.
This commit is contained in:
Neil Conway
2004-03-03 22:22:24 +00:00
parent 9e733eab69
commit c934cf1e96
4 changed files with 63 additions and 29 deletions
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27
doc/src/sgml/queries.sgml
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@@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/queries.sgml,v 1.28 2003/11/29 19:51:37 pgsql Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/queries.sgml,v 1.29 2004/03/03 22:22:24 neilc Exp $ -->
<chapter id="queries">
<title>Queries</title>
@@ -108,8 +108,9 @@ SELECT random();
<title>The <literal>FROM</literal> Clause</title>
<para>
The <literal>FROM</> clause derives a table from one or more other
tables given in a comma-separated table reference list.
The <xref linkend="sql-from" endterm="sql-from-title"> derives a
table from one or more other tables given in a comma-separated
table reference list.
<synopsis>
FROM <replaceable>table_reference</replaceable> <optional>, <replaceable>table_reference</replaceable> <optional>, ...</optional></optional>
</synopsis>
@@ -677,7 +678,8 @@ SELECT *
</indexterm>
<para>
The syntax of the <literal>WHERE</> clause is
The syntax of the <xref linkend="sql-where"
endterm="sql-where-title"> clause is
<synopsis>
WHERE <replaceable>search_condition</replaceable>
</synopsis>
@@ -783,13 +785,14 @@ SELECT <replaceable>select_list</replaceable>
</synopsis>
<para>
The <literal>GROUP BY</> clause is used to group together those rows in
a table that share the same values in all the columns listed. The
order in which the columns are listed does not matter. The
purpose is to reduce each group of rows sharing common values into
one group row that is representative of all rows in the group.
This is done to eliminate redundancy in the output and/or compute
aggregates that apply to these groups. For instance:
The <xref linkend="sql-groupby" endterm="sql-groupby-title"> is
used to group together those rows in a table that share the same
values in all the columns listed. The order in which the columns
are listed does not matter. The purpose is to reduce each group
of rows sharing common values into one group row that is
representative of all rows in the group. This is done to
eliminate redundancy in the output and/or compute aggregates that
apply to these groups. For instance:
<screen>
<prompt>=></> <userinput>SELECT * FROM test1;</>
x | y
@@ -1058,7 +1061,7 @@ SELECT a AS value, b + c AS sum FROM ...
<synopsis>
SELECT DISTINCT <replaceable>select_list</replaceable> ...
</synopsis>
(Instead of <literal>DISTINCT</> the word <literal>ALL</literal>
(Instead of <literal>DISTINCT</> the key word <literal>ALL</literal>
can be used to select the default behavior of retaining all rows.)
</para>