diff options
| -rw-r--r-- | doc/src/sgml/json.sgml | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/doc/src/sgml/json.sgml b/doc/src/sgml/json.sgml index 37dd611aeb7..8feb2fbf0ad 100644 --- a/doc/src/sgml/json.sgml +++ b/doc/src/sgml/json.sgml @@ -269,6 +269,12 @@ SELECT '"foo"'::jsonb @> '"foo"'::jsonb; -- The array on the right side is contained within the one on the left: SELECT '[1, 2, 3]'::jsonb @> '[1, 3]'::jsonb; +-- Order of array elements is not significant, so this is also true: +SELECT '[1, 2, 3]'::jsonb @> '[3, 1]'::jsonb; + +-- Duplicate array elements don't matter either: +SELECT '[1, 2, 3]'::jsonb @> '[1, 2, 2]'::jsonb; + -- The object with a single pair on the right side is contained -- within the object on the left side: SELECT '{"product": "PostgreSQL", "version": 9.4, "jsonb":true}'::jsonb @> '{"version":9.4}'::jsonb; @@ -288,8 +294,10 @@ SELECT '{"foo": {"bar": "baz"}}'::jsonb @> '{"bar": "baz"}'::jsonb; -- yields f The general principle is that the contained object must match the containing object as to structure and data contents, possibly after discarding some non-matching array elements or object key/value pairs - from the containing object. However, the order of array elements is - not significant when doing a containment match. + from the containing object. + But remember that the order of array elements is not significant when + doing a containment match, and duplicate array elements are effectively + considered only once. </para> <para> |