diff options
Diffstat (limited to 'doc/src/sgml/xoper.sgml')
| -rw-r--r-- | doc/src/sgml/xoper.sgml | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/doc/src/sgml/xoper.sgml b/doc/src/sgml/xoper.sgml index 56b08491c96..98f4c5c4aa4 100644 --- a/doc/src/sgml/xoper.sgml +++ b/doc/src/sgml/xoper.sgml @@ -20,8 +20,8 @@ </para> <para> - <productname>PostgreSQL</productname> supports left unary, right - unary, and binary operators. Operators can be + <productname>PostgreSQL</productname> supports prefix + and infix operators. Operators can be overloaded;<indexterm><primary>overloading</primary><secondary>operators</secondary></indexterm> that is, the same operator name can be used for different operators that have different numbers and types of operands. When a query is @@ -64,9 +64,9 @@ SELECT (a + b) AS c FROM test_complex; </para> <para> - We've shown how to create a binary operator here. To create unary - operators, just omit one of <literal>leftarg</literal> (for left unary) or - <literal>rightarg</literal> (for right unary). The <literal>function</literal> + We've shown how to create a binary operator here. To create a prefix + operator, just omit the <literal>leftarg</literal>. + The <literal>function</literal> clause and the argument clauses are the only required items in <command>CREATE OPERATOR</command>. The <literal>commutator</literal> clause shown in the example is an optional hint to the query @@ -202,7 +202,7 @@ SELECT (a + b) AS c FROM test_complex; <para> Unlike commutators, a pair of unary operators could validly be marked as each other's negators; that would mean (A x) equals NOT (B x) - for all x, or the equivalent for right unary operators. + for all x. </para> <para> |