feat: add support for engine

ch/query_test.go

@@ -134,6 +134,35 @@ func TestQuery(t *testing.T) {
 				OnCluster("my-cluster").
 				IfNotExists()
 		},
+		func(db *ch.DB) chschema.QueryAppender {
+			return db.NewCreateView().
+				Materialized().
+				Engine("MergeTree").
+				IfNotExists().
+				View("view_name").
+				Column("col1").
+				ColumnExpr("col1 AS alias").
+				TableExpr("src_table AS alias").
+				Where("foo = bar").
+				Group("group1").
+				GroupExpr("group2, group3").
+				OrderExpr("order2, order3")
+		},
+		func(db *ch.DB) chschema.QueryAppender {
+			return db.NewCreateView().
+				Materialized().
+				Engine("MergeTree").
+				To("dest_table"). // expect override engine
+				IfNotExists().
+				View("view_name").
+				Column("col1").
+				ColumnExpr("col1 AS alias").
+				TableExpr("src_table AS alias").
+				Where("foo = bar").
+				Group("group1").
+				GroupExpr("group2, group3").
+				OrderExpr("order2, order3")
+		},
 	}
 
 	db := chDB()
@@ -145,7 +174,6 @@ func TestQuery(t *testing.T) {
 	for i, fn := range queries {
 		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
 			q := fn(db)
-
 			query, err := q.AppendQuery(db.Formatter(), nil)
 			if err != nil {
 				snapshot.SnapshotT(t, err.Error())

ch/query_view_create.go

@@ -14,6 +14,7 @@ type CreateViewQuery struct {
 	materialized bool
 	ifNotExists  bool
 	view         chschema.QueryWithArgs
+	engine       chschema.QueryWithArgs
 	onCluster    chschema.QueryWithArgs
 	to           chschema.QueryWithArgs
 	where        whereQuery
@@ -62,6 +63,7 @@ func (q *CreateViewQuery) OnClusterExpr(query string, args ...any) *CreateViewQu
 	return q
 }
 
+// will disable engine option
 func (q *CreateViewQuery) To(to string) *CreateViewQuery {
 	q.to = chschema.UnsafeName(to)
 	return q
@@ -84,6 +86,11 @@ func (q *CreateViewQuery) TableExpr(query string, args ...any) *CreateViewQuery
 	return q
 }
 
+func (q *CreateViewQuery) Engine(query string, args ...any) *CreateViewQuery {
+	q.engine = chschema.SafeQuery(query, args)
+	return q
+}
+
 func (q *CreateViewQuery) ModelTableExpr(query string, args ...any) *CreateViewQuery {
 	q.modelTableName = chschema.SafeQuery(query, args)
 	return q
@@ -205,11 +212,24 @@ func (q *CreateViewQuery) AppendQuery(fmter chschema.Formatter, b []byte) (_ []b
 		}
 	}
 
-	b = append(b, " TO "...)
-	b, err = q.to.AppendQuery(fmter, b)
-	if err != nil {
-		return nil, err
+	if !q.to.IsEmpty() {
+		b = append(b, " TO "...)
+		b, err = q.to.AppendQuery(fmter, b)
+		if err != nil {
+			return nil, err
+		}
 	}
+
+	// clickhouse do not support both to and engine
+	if !q.engine.IsEmpty() && q.to.IsEmpty() {
+		b = append(b, " Engine = "...)
+
+		b, err = q.engine.AppendQuery(fmter, b)
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	b = append(b, " AS "...)
 
 	b = append(b, "SELECT "...)

ch/testdata/snapshots/TestQuery-20

@@ -0,0 +1 @@
+CREATE MATERIALIZED VIEW IF NOT EXISTS "view_name" Engine = MergeTree AS SELECT "col1", col1 AS alias FROM src_table AS alias WHERE (foo = bar) GROUP BY "group1", group2, group3 ORDER BY order2, order3

ch/testdata/snapshots/TestQuery-21

@@ -0,0 +1 @@
+CREATE MATERIALIZED VIEW IF NOT EXISTS "view_name" TO "dest_table" AS SELECT "col1", col1 AS alias FROM src_table AS alias WHERE (foo = bar) GROUP BY "group1", group2, group3 ORDER BY order2, order3