should be it

external/duckdb/test/sql/table_function/duckdb_constraints.test

@@ -0,0 +1,58 @@
+# name: test/sql/table_function/duckdb_constraints.test
+# description: Test duckdb_constraints function
+# group: [table_function]
+
+statement ok
+create table integers(i int primary key, check (i < 10));
+
+statement ok
+create table test(i varchar unique, k varchar, check(len(i || k) < 10));
+
+statement ok
+create table fk_integers(j int, foreign key (j) references integers(i));
+
+statement ok
+create table fk_integers_2(k int, foreign key (k) references integers(i));
+
+statement ok nosort duckdb_col
+SELECT * FROM duckdb_constraints();
+
+statement ok nosort duckdb_col
+SELECT * FROM duckdb_constraints;
+
+query IIII
+SELECT table_name, constraint_index, constraint_type, UNNEST(constraint_column_names) col_name FROM duckdb_constraints ORDER BY table_name, constraint_index, col_name
+----
+fk_integers	0	FOREIGN KEY	j
+fk_integers_2	1	FOREIGN KEY	k
+integers	2	PRIMARY KEY	i
+integers	3	CHECK	i
+integers	4	NOT NULL	i
+test	5	UNIQUE	i
+test	6	CHECK	i
+test	6	CHECK	k
+
+query II
+SELECT constraint_name, unique_constraint_name FROM information_schema.referential_constraints ORDER BY constraint_name
+----
+fk_integers_2_k_i_fkey	integers_i_pkey
+fk_integers_j_i_fkey	integers_i_pkey
+
+query IIII
+SELECT column_name, constraint_name, table_name, position_in_unique_constraint FROM information_schema.key_column_usage ORDER BY constraint_name
+----
+k	fk_integers_2_k_i_fkey	fk_integers_2	1
+j	fk_integers_j_i_fkey	fk_integers	1
+i	integers_i_pkey	integers	NULL
+i	test_i_key	test	NULL
+
+query III
+SELECT constraint_name, table_name, constraint_type FROM information_schema.table_constraints ORDER BY constraint_name;
+----
+fk_integers_2_k_i_fkey	fk_integers_2	FOREIGN KEY
+fk_integers_j_i_fkey	fk_integers	FOREIGN KEY
+integers_i_check	integers	CHECK
+integers_i_not_null	integers	CHECK
+integers_i_pkey	integers	PRIMARY KEY
+test_i_k_check	test	CHECK
+test_i_key	test	UNIQUE