diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 5b1a2b4190..1ef25bcbce 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -12733,14 +12733,14 @@ SELECT NULLIF(value, '(none)') ... @> contains - ARRAY[1,4,3] @> ARRAY[3,1] + ARRAY[1,4,3] @> ARRAY[3,1,3] t <@ is contained by - ARRAY[2,7] <@ ARRAY[1,7,4,2,6] + ARRAY[2,2,7] <@ ARRAY[1,7,4,2,6] t @@ -12783,8 +12783,10 @@ SELECT NULLIF(value, '(none)') ... - Array comparisons compare the array contents element-by-element, - using the default B-tree comparison function for the element data type. + The array ordering operators (<, + >=, etc) compare the array contents + element-by-element, using the default B-tree comparison function for + the element data type, and sort based on the first difference. In multidimensional arrays the elements are visited in row-major order (last subscript varies most rapidly). If the contents of two arrays are equal but the dimensionality is @@ -12795,6 +12797,15 @@ SELECT NULLIF(value, '(none)') ... number of dimensions or subscript ranges were different.) + + The array containment operators (<@ + and @>) consider one array to be contained in + another one if each of its elements appears in the other one. + Duplicates are not treated specially, thus ARRAY[1] + and ARRAY[1,1] are each considered to contain the + other. + + See for more details about array operator behavior. See for more details about