Fix typo

Reported by Robins Tharakan

Author: mhagander

src/backend/parser/parse_utilcmd.c

@@ -672,7 +672,7 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column)
 					if (cxt->partbound)
 						ereport(ERROR,
 								(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-								 errmsg("identify columns are not supported on partitions")));
+								 errmsg("identity columns are not supported on partitions")));
 
 					ctype = typenameType(cxt->pstate, column->typeName, NULL);
 					typeOid = HeapTupleGetOid(ctype);

src/test/regress/expected/identity.out

@@ -356,5 +356,5 @@ CREATE TABLE itest_parent (f1 date NOT NULL, f2 text, f3 bigint) PARTITION BY RA
 CREATE TABLE itest_child PARTITION OF itest_parent (
     f3 WITH OPTIONS GENERATED ALWAYS AS IDENTITY
 ) FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
-ERROR:  identify columns are not supported on partitions
+ERROR:  identity columns are not supported on partitions
 DROP TABLE itest_parent;