Enable materialized CTEs in INSERT statements

src/parser/transform/statement/transform_insert.cpp

@@ -28,9 +28,6 @@ unique_ptr<InsertStatement> Transformer::TransformInsert(duckdb_libpgquery::PGIn
 	if (stmt.withClause) {
 		TransformCTE(*PGPointerCast<duckdb_libpgquery::PGWithClause>(stmt.withClause), result->cte_map,
 		             materialized_ctes);
-		if (!materialized_ctes.empty()) {
-			throw NotImplementedException("Materialized CTEs are not implemented for insert.");
-		}
 	}
 
 	// first check if there are any columns specified
@@ -47,6 +44,7 @@ unique_ptr<InsertStatement> Transformer::TransformInsert(duckdb_libpgquery::PGIn
 	}
 	if (stmt.selectStmt) {
 		result->select_statement = TransformSelect(stmt.selectStmt, false);
+		result->select_statement->node = TransformMaterializedCTE(std::move(result->select_statement->node), materialized_ctes);
 	} else {
 		result->default_values = true;
 	}

test/sql/catalog/function/test_cte_macro.test

@@ -40,9 +40,6 @@ SELECT plus42(42)
 ----
 84
 
-# temporary solution until decorrelation of materialized CTEs is implemented
-require noalternativeverify
-
 query T
 SELECT plus42(a) FROM integers
 ----

test/sql/cte/materialized/dml_materialized_cte.test

@@ -13,10 +13,9 @@ create table a(i integer);
 statement ok
 insert into a values (42);
 
-statement error
+statement ok
 WITH t(x) AS MATERIALIZED (VALUES (42))
 INSERT INTO a (SELECT * FROM t);
-----
 
 statement error
 WITH t(x) AS MATERIALIZED (VALUES (42))

test/sql/subquery/scalar/test_correlated_subquery.test

@@ -14,9 +14,6 @@ CREATE TABLE integers(i INTEGER)
 statement ok
 INSERT INTO integers VALUES (1), (2), (3), (NULL)
 
-# temporary solution until decorrelation of materialized CTEs is implemented
-require noalternativeverify
-
 # scalar select with correlation
 query II
 SELECT i, (SELECT 42+i1.i) AS j FROM integers i1 ORDER BY i;