diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/intarray.sgml | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/doc/src/sgml/intarray.sgml b/doc/src/sgml/intarray.sgml index 1cf72a12010..449878d6716 100644 --- a/doc/src/sgml/intarray.sgml +++ b/doc/src/sgml/intarray.sgml @@ -9,10 +9,21 @@ <para> The <filename>intarray</> module provides a number of useful functions - and operators for manipulating one-dimensional arrays of integers. + and operators for manipulating null-free arrays of integers. There is also support for indexed searches using some of the operators. </para> + <para> + All of these operations will throw an error if a supplied array contains any + NULL elements. + </para> + + <para> + Many of these operations are only sensible for one-dimensional arrays. + Although they will accept input arrays of more dimensions, the data is + treated as though it were a linear array in storage order. + </para> + <sect2> <title><filename>intarray</> Functions and Operators</title> @@ -211,14 +222,12 @@ </para> <para> - The containment operators <literal>@></> and <literal><@</> are - approximately equivalent to <productname>PostgreSQL</>'s built-in operators - of the same names, except that they work only on integer arrays while the - built-in operators work for any array type. An important difference is - that <filename>intarray</>'s operators do not consider an empty array to be - contained in anything else. This is consistent with the behavior of - GIN-indexed queries, but not with the usual mathematical definition of - containment. + The operators <literal>&&</>, <literal>@></> and + <literal><@</> are equivalent to <productname>PostgreSQL</>'s built-in + operators of the same names, except that they work only on integer arrays + that do not contain nulls, while the built-in operators work for any array + type. This restriction makes them faster than the built-in operators + in many cases. </para> <para> |