planner, executor: support create view on union

executor/ddl_test.go

@@ -29,6 +29,7 @@ import (
 	"github.com/pingcap/tidb/ddl"
 	ddlutil "github.com/pingcap/tidb/ddl/util"
 	"github.com/pingcap/tidb/domain"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/meta"
 	"github.com/pingcap/tidb/meta/autoid"
@@ -224,6 +225,33 @@ func (s *testSuite6) TestCreateView(c *C) {
 	// create view using prepare
 	tk.MustExec(`prepare stmt from "create view v10 (x) as select 1";`)
 	tk.MustExec("execute stmt")
+
+	// create view on union
+	tk.MustExec("drop table if exists t1, t2")
+	tk.MustExec("drop view if exists v")
+	_, err = tk.Exec("create view v as select * from t1 union select * from t2")
+	c.Assert(terror.ErrorEqual(err, infoschema.ErrTableNotExists), IsTrue)
+	tk.MustExec("create table t1(a int, b int)")
+	tk.MustExec("create table t2(a int, b int)")
+	tk.MustExec("insert into t1 values(1,2), (1,1), (1,2)")
+	tk.MustExec("insert into t2 values(1,1),(1,3)")
+	tk.MustExec("create definer='root'@'localhost' view v as select * from t1 union select * from t2")
+	tk.MustQuery("select * from v").Sort().Check(testkit.Rows("1 1", "1 2", "1 3"))
+	tk.MustExec("alter table t1 drop column a")
+	_, err = tk.Exec("select * from v")
+	c.Assert(terror.ErrorEqual(err, plannercore.ErrViewInvalid), IsTrue)
+	tk.MustExec("alter table t1 add column a int")
+	tk.MustQuery("select * from v").Sort().Check(testkit.Rows("1 1", "1 3", "<nil> 1", "<nil> 2"))
+	tk.MustExec("alter table t1 drop column a")
+	tk.MustExec("alter table t2 drop column b")
+	_, err = tk.Exec("select * from v")
+	c.Assert(terror.ErrorEqual(err, plannercore.ErrViewInvalid), IsTrue)
+	tk.MustExec("drop view v")
+
+	tk.MustExec("create view v as (select * from t1)")
+	tk.MustExec("drop view v")
+	tk.MustExec("create view v as (select * from t1 union select * from t2)")
+	tk.MustExec("drop view v")
 }
 
 func (s *testSuite6) TestCreateDropDatabase(c *C) {

executor/executor_test.go

@@ -3826,11 +3826,11 @@ func (s *testSuite) TestSelectView(c *C) {
 	tk.MustExec("drop table view_t;")
 	tk.MustExec("create table view_t(c int,d int)")
 	err := tk.ExecToErr("select * from view1")
-	c.Assert(err.Error(), Equals, "[planner:1054]Unknown column 'test.view_t.a' in 'field list'")
+	c.Assert(err.Error(), Equals, "[planner:1356]View 'test.view1' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them")
 	err = tk.ExecToErr("select * from view2")
-	c.Assert(err.Error(), Equals, "[planner:1054]Unknown column 'test.view_t.a' in 'field list'")
+	c.Assert(err.Error(), Equals, "[planner:1356]View 'test.view2' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them")
 	err = tk.ExecToErr("select * from view3")
-	c.Assert(err.Error(), Equals, "[planner:1054]Unknown column 'a' in 'field list'")
+	c.Assert(err.Error(), Equals, plannercore.ErrViewInvalid.GenWithStackByArgs("test", "view3").Error())
 	tk.MustExec("drop table view_t;")
 	tk.MustExec("create table view_t(a int,b int,c int)")
 	tk.MustExec("insert into view_t values(1,2,3)")

go.sum

@@ -190,7 +190,6 @@ github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d h1:GoAlyOgbOEIFd
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/remyoudompheng/bigfft v0.0.0-20190512091148-babf20351dd7 h1:FUL3b97ZY2EPqg2NbXKuMHs5pXJB9hjj1fDHnF2vl28=
 github.com/remyoudompheng/bigfft v0.0.0-20190512091148-babf20351dd7/go.mod h1:qqbHyh8v60DhA7CoWK5oRCqLrMHRGoxYCSS9EjAz6Eo=
-github.com/sergi/go-diff v1.0.1-0.20180205163309-da645544ed44 h1:tB9NOR21++IjLyVx3/PCPhWMwqGNCMQEH96A6dMZ/gc=
 github.com/sergi/go-diff v1.0.1-0.20180205163309-da645544ed44/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
 github.com/shirou/gopsutil v2.18.10+incompatible h1:cy84jW6EVRPa5g9HAHrlbxMSIjBhDSX0OFYyMYminYs=
 github.com/shirou/gopsutil v2.18.10+incompatible/go.mod h1:5b4v6he4MtMOwMlS0TUMTu2PcXUg8+E1lC7eC3UO/RA=

planner/core/logical_plan_builder.go

@@ -2470,6 +2470,7 @@ func (b *PlanBuilder) BuildDataSourceFromView(ctx context.Context, dbName model.
 	b.visitInfo = make([]visitInfo, 0)
 	selectLogicalPlan, err := b.Build(ctx, selectNode)
 	if err != nil {
+		err = ErrViewInvalid.GenWithStackByArgs(dbName.O, tableInfo.Name.O)
 		return nil, err
 	}