dialect/sql: add support for setting the table_schema in select_table (#1001)

dialect/sql/builder.go

@@ -1382,9 +1382,10 @@ type TableView interface {
 // SelectTable is a table selector.
 type SelectTable struct {
 	Builder
-	quote bool
-	name  string
-	as    string
+	as     string
+	name   string
+	schema string
+	quote  bool
 }
 
 // Table returns a new table selector.
@@ -1396,6 +1397,12 @@ func Table(name string) *SelectTable {
 	return &SelectTable{quote: true, name: name}
 }
 
+// Schema sets the schema name of the table.
+func (s *SelectTable) Schema(name string) *SelectTable {
+	s.schema = name
+	return s
+}
+
 // As adds the AS clause to the table selector.
 func (s *SelectTable) As(alias string) *SelectTable {
 	s.as = alias
@@ -1409,9 +1416,10 @@ func (s *SelectTable) C(column string) string {
 		name = s.as
 	}
 	b := &Builder{dialect: s.dialect}
-	b.Ident(name)
-	b.WriteByte('.')
-	b.Ident(column)
+	if s.schema != "" && s.as == "" {
+		b.Ident(s.schema).WriteByte('.')
+	}
+	b.Ident(name).WriteByte('.').Ident(column)
 	return b.String()
 }
 
@@ -1438,6 +1446,9 @@ func (s *SelectTable) ref() string {
 		return s.name
 	}
 	b := &Builder{dialect: s.dialect}
+	if s.schema != "" {
+		b.Ident(s.schema).WriteByte('.')
+	}
 	b.Ident(s.name)
 	if s.as != "" {
 		b.WriteString(" AS ")

dialect/sql/builder_test.go

@@ -680,8 +680,8 @@ func TestBuilder(t *testing.T) {
 				return Select(t1.C("id"), As(Count("`*`"), "group_count")).
 					From(t1).
 					LeftJoin(t2).
-					OnP(P(func(builder *Builder) {
-						builder.Ident(t1.C("id")).WriteOp(OpEQ).Ident(t2.C("user_id"))
+					OnP(P(func(b *Builder) {
+						b.Ident(t1.C("id")).WriteOp(OpEQ).Ident(t2.C("user_id"))
 					})).
 					GroupBy(t1.C("id")).Clone()
 			}(),
@@ -1271,6 +1271,19 @@ WHERE
 			wantQuery: `SELECT * FROM "test" WHERE nlevel("path") > $1`,
 			wantArgs:  []interface{}{1},
 		},
+		{
+			input: func() Querier {
+				t1, t2 := Table("users").Schema("s1"), Table("pets").Schema("s2")
+				return Select("*").
+					From(t1).Join(t2).
+					OnP(P(func(b *Builder) {
+						b.Ident(t1.C("id")).WriteOp(OpEQ).Ident(t2.C("owner_id"))
+					})).
+					Where(EQ(t2.C("name"), "pedro"))
+			}(),
+			wantQuery: "SELECT * FROM `s1`.`users` JOIN `s2`.`pets` AS `t0` ON `s1`.`users`.`id` = `t0`.`owner_id` WHERE `t0`.`name` = ?",
+			wantArgs:  []interface{}{"pedro"},
+		},
 	}
 	for i, tt := range tests {
 		t.Run(strconv.Itoa(i), func(t *testing.T) {