diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/func.sgml | 17 | ||||
| -rw-r--r-- | doc/src/sgml/syntax.sgml | 4 |
2 files changed, 18 insertions, 3 deletions
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index dc646320cb9..00d476edb6f 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -1,4 +1,4 @@ -<!-- $Header: /cvsroot/pgsql/doc/src/sgml/func.sgml,v 1.61 2001/06/15 21:03:07 tgl Exp $ --> +<!-- $Header: /cvsroot/pgsql/doc/src/sgml/func.sgml,v 1.62 2001/06/19 22:39:08 tgl Exp $ --> <chapter id="functions"> <title>Functions and Operators</title> @@ -273,6 +273,21 @@ <productname>Microsoft Access</productname>) to work, but this may be discontinued in a future release. </para> + + <para> + Boolean values can be tested using the constructs +<synopsis> +<replaceable>expression</replaceable> IS TRUE +<replaceable>expression</replaceable> IS NOT TRUE +<replaceable>expression</replaceable> IS FALSE +<replaceable>expression</replaceable> IS NOT FALSE +<replaceable>expression</replaceable> IS UNKNOWN +<replaceable>expression</replaceable> IS NOT UNKNOWN +</synopsis> + These are similar to <literal>IS NULL</literal> in that they will + always return TRUE or FALSE, never NULL, even when the operand is NULL. + A NULL input is treated as the logical value UNKNOWN. + </para> </sect1> diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml index 9234e3c26d4..300851235ca 100644 --- a/doc/src/sgml/syntax.sgml +++ b/doc/src/sgml/syntax.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.42 2001/05/12 22:51:35 petere Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.43 2001/06/19 22:39:08 tgl Exp $ --> <chapter id="sql-syntax"> @@ -1060,7 +1060,7 @@ SELECT (5 !) - 6; <row> <entry><token>IS</token></entry> <entry></entry> - <entry>test for TRUE, FALSE, NULL</entry> + <entry>test for TRUE, FALSE, UNKNOWN, NULL</entry> </row> <row> |