diff options
| -rw-r--r-- | doc/src/sgml/json.sgml | 3 | ||||
| -rw-r--r-- | src/backend/utils/adt/jsonb_util.c | 7 |
2 files changed, 9 insertions, 1 deletions
diff --git a/doc/src/sgml/json.sgml b/doc/src/sgml/json.sgml index 54648c459c1..206eadb8f7b 100644 --- a/doc/src/sgml/json.sgml +++ b/doc/src/sgml/json.sgml @@ -584,12 +584,13 @@ SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc @@ '$.tags[*] == "qui"'; The <literal>btree</literal> ordering for <type>jsonb</type> datums is seldom of great interest, but for completeness it is: <synopsis> -<replaceable>Object</replaceable> > <replaceable>Array</replaceable> > <replaceable>Boolean</replaceable> > <replaceable>Number</replaceable> > <replaceable>String</replaceable> > <replaceable>Null</replaceable> +<replaceable>Object</replaceable> > <replaceable>Array</replaceable> > <replaceable>Boolean</replaceable> > <replaceable>Number</replaceable> > <replaceable>String</replaceable> > <replaceable>null</replaceable> <replaceable>Object with n pairs</replaceable> > <replaceable>object with n - 1 pairs</replaceable> <replaceable>Array with n elements</replaceable> > <replaceable>array with n - 1 elements</replaceable> </synopsis> + with the exception that (for historical reasons) an empty top level array sorts less than <replaceable>null</replaceable>. Objects with equal numbers of pairs are compared in the order: <synopsis> <replaceable>key-1</replaceable>, <replaceable>value-1</replaceable>, <replaceable>key-2</replaceable> ... diff --git a/src/backend/utils/adt/jsonb_util.c b/src/backend/utils/adt/jsonb_util.c index 806d1aa3a98..773f3690c7b 100644 --- a/src/backend/utils/adt/jsonb_util.c +++ b/src/backend/utils/adt/jsonb_util.c @@ -246,6 +246,13 @@ compareJsonbContainers(JsonbContainer *a, JsonbContainer *b) */ if (va.val.array.rawScalar != vb.val.array.rawScalar) res = (va.val.array.rawScalar) ? -1 : 1; + + /* + * There should be an "else" here, to prevent us from + * overriding the above, but we can't change the sort + * order now, so there is a mild anomaly that an empty + * top level array sorts less than null. + */ if (va.val.array.nElems != vb.val.array.nElems) res = (va.val.array.nElems > vb.val.array.nElems) ? 1 : -1; break; |