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A small pass of docs review and copy-editing.

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This commit is contained in:
Tom Lane
2004-12-23 05:37:40 +00:00
parent 3621657a61
commit f8ffb60492
9 changed files with 171 additions and 128 deletions
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20
doc/src/sgml/syntax.sgml
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@@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.98 2004/12/13 18:05:09 petere Exp $
$PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.99 2004/12/23 05:37:40 tgl Exp $
-->
<chapter id="sql-syntax">
@@ -599,7 +599,8 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
A dollar sign (<literal>$</literal>) followed by digits is used
to represent a positional parameter in the body of a function
definition or a prepared statement. In other contexts the
dollar sign may be part of an identifier.
dollar sign may be part of an identifier or a dollar-quoted string
constant.
</para>
</listitem>
@@ -646,8 +647,9 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
<listitem>
<para>
The asterisk (<literal>*</literal>) has a special meaning when
used in the <command>SELECT</command> command or with the
The asterisk (<literal>*</literal>) is used in some contexts to denote
all the fields of a table row or composite value. It also
has a special meaning when used as the argument of the
<function>COUNT</function> aggregate function.
</para>
</listitem>
@@ -823,7 +825,7 @@ SELECT (5 !) - 6;
<row>
<entry><token>BETWEEN</token></entry>
<entry></entry>
<entry>containment</entry>
<entry>range containment</entry>
</row>
<row>
@@ -1083,7 +1085,7 @@ $<replaceable>number</replaceable>
<programlisting>
CREATE FUNCTION dept(text) RETURNS dept
AS $$SELECT * FROM dept WHERE name = $1$$
AS $$ SELECT * FROM dept WHERE name = $1 $$
LANGUAGE SQL;
</programlisting>
@@ -1552,7 +1554,9 @@ SELECT ROW(1,2.5,'this is a test');
to avoid ambiguity. For example:
<programlisting>
CREATE TABLE mytable(f1 int, f2 float, f3 text);
CREATE FUNCTION getf1(mytable) RETURNS int AS 'SELECT $1.f1' LANGUAGE SQL;
-- No cast needed since only one getf1() exists
SELECT getf1(ROW(1,2.5,'this is a test'));
getf1
@@ -1561,10 +1565,13 @@ SELECT getf1(ROW(1,2.5,'this is a test'));
(1 row)
CREATE TYPE myrowtype AS (f1 int, f2 text, f3 numeric);
CREATE FUNCTION getf1(myrowtype) RETURNS int AS 'SELECT $1.f1' LANGUAGE SQL;
-- Now we need a cast to indicate which function to call:
SELECT getf1(ROW(1,2.5,'this is a test'));
ERROR: function getf1(record) is not unique
SELECT getf1(ROW(1,2.5,'this is a test')::mytable);
getf1
-------
@@ -1587,6 +1594,7 @@ SELECT getf1(CAST(ROW(11,'this is a test',2.5) AS myrowtype));
<literal>IS NULL</> or <literal>IS NOT NULL</>, for example
<programlisting>
SELECT ROW(1,2.5,'this is a test') = ROW(1, 3, 'not the same');
SELECT ROW(a, b, c) IS NOT NULL FROM table;
</programlisting>
For more detail see <xref linkend="functions-comparisons">.