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More editing of reference pages.

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This commit is contained in:
Peter Eisentraut
2003-04-22 10:08:08 +00:00
parent 8a703496a2
commit 3450fd08a9
21 changed files with 2561 additions and 3612 deletions
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41
doc/src/sgml/ref/create_cast.sgml
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@@ -1,4 +1,4 @@
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/create_cast.sgml,v 1.10 2003/03/25 16:15:39 petere Exp $ -->
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/create_cast.sgml,v 1.11 2003/04/22 10:08:08 petere Exp $ -->
<refentry id="SQL-CREATECAST">
<refmeta>
@@ -58,11 +58,11 @@ SELECT CAST(42 AS text);
<para>
If the cast is marked <literal>AS ASSIGNMENT</> then it can be invoked
implicitly when assigning to a column of the target data type.
implicitly when assigning a value to a column of the target data type.
For example, supposing that <literal>foo.f1</literal> is a column of
type <type>text</type>, then
<programlisting>
INSERT INTO foo(f1) VALUES(42);
INSERT INTO foo (f1) VALUES (42);
</programlisting>
will be allowed if the cast from type <type>integer</type> to type
<type>text</type> is marked <literal>AS ASSIGNMENT</>, otherwise
@@ -75,7 +75,7 @@ INSERT INTO foo(f1) VALUES(42);
If the cast is marked <literal>AS IMPLICIT</> then it can be invoked
implicitly in any context, whether assignment or internally in an
expression. For example, since <literal>||</> takes <type>text</>
arguments,
operands,
<programlisting>
SELECT 'The time is ' || now();
</programlisting>
@@ -106,14 +106,16 @@ SELECT 'The time is ' || CAST(now() AS text);
<para>
To be able to create a cast, you must own the source or the target
data type. To create a binary-compatible cast, you must be superuser
(this restriction is made because an erroneous binary-compatible cast
conversion can easily crash the server).
data type. To create a binary-compatible cast, you must be superuser.
(This restriction is made because an erroneous binary-compatible cast
conversion can easily crash the server.)
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<title>Parameters</title>
<varlistentry>
<term><replaceable>sourcetype</replaceable></term>
@@ -183,6 +185,21 @@ SELECT 'The time is ' || CAST(now() AS text);
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>CREATE CAST</computeroutput></term>
<listitem>
<para>
Message returned if the cast was successfully created.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="sql-createcast-notes">
<title>Notes</title>
@@ -201,8 +218,8 @@ SELECT 'The time is ' || CAST(now() AS text);
argument of a different type was automatically a cast function.
This convention has been abandoned in face of the introduction of
schemas and to be able to represent binary compatible casts in the
catalogs. (The built-in cast functions still follow this naming
scheme, but they have to be shown as casts in <literal>pg_cast</>
system catalogs. (The built-in cast functions still follow this naming
scheme, but they have to be shown as casts in the system catalog <literal>pg_cast</>
now.)
</para>
</refsect1>
@@ -227,7 +244,7 @@ CREATE CAST (text AS int4) WITH FUNCTION int4(text);
<para>
The <command>CREATE CAST</command> command conforms to SQL99,
except that SQL99 does not make provisions for binary compatible
except that SQL99 does not make provisions for binary-compatible
types. <literal>AS IMPLICIT</> is a <productname>PostgreSQL</productname>
extension, too.
</para>