*: Add SHOW PLACEMENT support for tables (#28266)

ddl/placement_policy_test.go

@@ -219,7 +219,7 @@ func (s *testDBSuite6) TestConstraintCompatibility(c *C) {
 			err := tk.ExecToErr(sql)
 			c.Assert(err, NotNil)
 			c.Assert(err.Error(), Equals, ca.errmsg)
-			tk.MustQuery("show placement where target='POLICY x'").Check(testkit.Rows("POLICY x REGIONS=\"cn-east1,cn-east\" SCHEDULED"))
+			tk.MustQuery("show placement where target='POLICY x'").Check(testkit.Rows("POLICY x REGIONS=\"cn-east1,cn-east\""))
 		}
 	}
 	tk.MustExec("drop placement policy x")
@@ -234,20 +234,20 @@ func (s *testDBSuite6) TestAlterPlacementPolicy(c *C) {
 
 	// test for normal cases
 	tk.MustExec("alter placement policy x REGIONS=\"bj,sh\"")
-	tk.MustQuery("show placement where target='POLICY x'").Check(testkit.Rows("POLICY x REGIONS=\"bj,sh\" SCHEDULED"))
+	tk.MustQuery("show placement where target='POLICY x'").Check(testkit.Rows("POLICY x REGIONS=\"bj,sh\""))
 
 	tk.MustExec("alter placement policy x " +
 		"PRIMARY_REGION=\"bj\" " +
 		"REGIONS=\"sh\" " +
 		"SCHEDULE=\"EVEN\"")
-	tk.MustQuery("show placement where target='POLICY x'").Check(testkit.Rows("POLICY x PRIMARY_REGION=\"bj\" REGIONS=\"sh\" SCHEDULE=\"EVEN\" SCHEDULED"))
+	tk.MustQuery("show placement where target='POLICY x'").Check(testkit.Rows("POLICY x PRIMARY_REGION=\"bj\" REGIONS=\"sh\" SCHEDULE=\"EVEN\""))
 
 	tk.MustExec("alter placement policy x " +
 		"LEADER_CONSTRAINTS=\"[+region=us-east-1]\" " +
 		"FOLLOWER_CONSTRAINTS=\"[+region=us-east-2]\" " +
 		"FOLLOWERS=3")
 	tk.MustQuery("show placement where target='POLICY x'").Check(
-		testkit.Rows("POLICY x LEADER_CONSTRAINTS=\"[+region=us-east-1]\" FOLLOWERS=3 FOLLOWER_CONSTRAINTS=\"[+region=us-east-2]\" SCHEDULED"),
+		testkit.Rows("POLICY x LEADER_CONSTRAINTS=\"[+region=us-east-1]\" FOLLOWERS=3 FOLLOWER_CONSTRAINTS=\"[+region=us-east-2]\""),
 	)
 
 	tk.MustExec("alter placement policy x " +
@@ -257,7 +257,7 @@ func (s *testDBSuite6) TestAlterPlacementPolicy(c *C) {
 		"VOTERS=5 " +
 		"LEARNERS=3")
 	tk.MustQuery("show placement where target='POLICY x'").Check(
-		testkit.Rows("POLICY x CONSTRAINTS=\"[+disk=ssd]\" VOTERS=5 VOTER_CONSTRAINTS=\"[+region=bj]\" LEARNERS=3 LEARNER_CONSTRAINTS=\"[+region=sh]\" SCHEDULED"),
+		testkit.Rows("POLICY x CONSTRAINTS=\"[+disk=ssd]\" VOTERS=5 VOTER_CONSTRAINTS=\"[+region=bj]\" LEARNERS=3 LEARNER_CONSTRAINTS=\"[+region=sh]\""),
 	)
 
 	// test alter not exist policies
@@ -472,7 +472,7 @@ func (s *testDBSuite6) TestPolicyCacheAndPolicyDependencyCache(c *C) {
 	tk.MustExec("create placement policy x primary_region=\"r1\" regions=\"r1,r2\" schedule=\"EVEN\";")
 	po := testGetPolicyByName(c, tk.Se, "x", true)
 	c.Assert(po, NotNil)
-	tk.MustQuery("show placement").Check(testkit.Rows("POLICY x PRIMARY_REGION=\"r1\" REGIONS=\"r1,r2\" SCHEDULE=\"EVEN\" SCHEDULED"))
+	tk.MustQuery("show placement").Check(testkit.Rows("POLICY x PRIMARY_REGION=\"r1\" REGIONS=\"r1,r2\" SCHEDULE=\"EVEN\""))
 
 	tk.MustExec("drop table if exists t")
 	tk.MustExec("create table t (a int) placement policy \"x\"")

ddl/placement_sql_test.go

@@ -736,8 +736,8 @@ func (s *testDBSuite6) TestCreateSchemaWithPlacement(c *C) {
 
 	tk.MustExec(`CREATE PLACEMENT POLICY PolicySchemaTest LEADER_CONSTRAINTS = "[+region=nl]" FOLLOWER_CONSTRAINTS="[+region=se]" FOLLOWERS=4 LEARNER_CONSTRAINTS="[+region=be]" LEARNERS=4`)
 	tk.MustExec(`CREATE PLACEMENT POLICY PolicyTableTest LEADER_CONSTRAINTS = "[+region=tl]" FOLLOWER_CONSTRAINTS="[+region=tf]" FOLLOWERS=2 LEARNER_CONSTRAINTS="[+region=tle]" LEARNERS=1`)
-	tk.MustQuery("SHOW PLACEMENT like 'POLICY %PolicySchemaTest%'").Check(testkit.Rows("POLICY PolicySchemaTest LEADER_CONSTRAINTS=\"[+region=nl]\" FOLLOWERS=4 FOLLOWER_CONSTRAINTS=\"[+region=se]\" LEARNERS=4 LEARNER_CONSTRAINTS=\"[+region=be]\" SCHEDULED"))
-	tk.MustQuery("SHOW PLACEMENT like 'POLICY %PolicyTableTest%'").Check(testkit.Rows("POLICY PolicyTableTest LEADER_CONSTRAINTS=\"[+region=tl]\" FOLLOWERS=2 FOLLOWER_CONSTRAINTS=\"[+region=tf]\" LEARNERS=1 LEARNER_CONSTRAINTS=\"[+region=tle]\" SCHEDULED"))
+	tk.MustQuery("SHOW PLACEMENT like 'POLICY %PolicySchemaTest%'").Check(testkit.Rows("POLICY PolicySchemaTest LEADER_CONSTRAINTS=\"[+region=nl]\" FOLLOWERS=4 FOLLOWER_CONSTRAINTS=\"[+region=se]\" LEARNERS=4 LEARNER_CONSTRAINTS=\"[+region=be]\""))
+	tk.MustQuery("SHOW PLACEMENT like 'POLICY %PolicyTableTest%'").Check(testkit.Rows("POLICY PolicyTableTest LEADER_CONSTRAINTS=\"[+region=tl]\" FOLLOWERS=2 FOLLOWER_CONSTRAINTS=\"[+region=tf]\" LEARNERS=1 LEARNER_CONSTRAINTS=\"[+region=tle]\""))
 	tk.MustExec("CREATE SCHEMA SchemaPolicyPlacementTest PLACEMENT POLICY = `PolicySchemaTest`")
 	tk.MustQuery("SHOW CREATE SCHEMA SCHEMAPOLICYPLACEMENTTEST").Check(testkit.Rows("SchemaPolicyPlacementTest CREATE DATABASE `SchemaPolicyPlacementTest` /*!40100 DEFAULT CHARACTER SET utf8mb4 */ PLACEMENT POLICY = `PolicySchemaTest`"))
 

executor/show.go

@@ -218,6 +218,8 @@ func (e *ShowExec) fetchAll(ctx context.Context) error {
 		return e.fetchShowPlacementLabels(ctx)
 	case ast.ShowPlacement:
 		return e.fetchShowPlacement(ctx)
+	case ast.ShowPlacementForTable:
+		return e.fetchShowPlacementForTable(ctx)
 	}
 	return nil
 }

executor/show_placement.go

@@ -20,7 +20,11 @@ import (
 	"sort"
 
 	"github.com/pingcap/errors"
+	"github.com/pingcap/parser/ast"
+	"github.com/pingcap/parser/model"
+	"github.com/pingcap/parser/mysql"
 	"github.com/pingcap/tidb/infoschema"
+	"github.com/pingcap/tidb/privilege"
 	"github.com/pingcap/tidb/store/helper"
 	"github.com/pingcap/tidb/types/json"
 	"github.com/pingcap/tidb/util/sqlexec"
@@ -128,23 +132,117 @@ func (e *ShowExec) fetchShowPlacementLabels(ctx context.Context) error {
 	return nil
 }
 
-func (e *ShowExec) fetchShowPlacement(_ context.Context) error {
-	err := e.fetchAllPlacementPolicies()
+func (e *ShowExec) fetchShowPlacementForTable(_ context.Context) (err error) {
+	tbl, err := e.getTable()
+	if err != nil {
+		return err
+	}
+
+	tblInfo := tbl.Meta()
+	placement, err := e.getTablePlacement(tblInfo)
 	if err != nil {
 		return err
 	}
 
+	if placement != nil {
+		ident := ast.Ident{Schema: e.Table.DBInfo.Name, Name: tblInfo.Name}
+		e.appendRow([]interface{}{"TABLE " + ident.String(), placement.String()})
+	}
+
 	return nil
 }
 
+func (e *ShowExec) fetchShowPlacement(_ context.Context) error {
+	if err := e.fetchAllPlacementPolicies(); err != nil {
+		return err
+	}
+
+	return e.fetchAllTablePlacements()
+}
+
 func (e *ShowExec) fetchAllPlacementPolicies() error {
 	policies := e.is.AllPlacementPolicies()
 	sort.Slice(policies, func(i, j int) bool { return policies[i].Name.O < policies[j].Name.O })
 	for _, policy := range policies {
 		name := policy.Name
 		settings := policy.PlacementSettings
-		e.appendRow([]interface{}{"POLICY " + name.String(), settings.String(), "SCHEDULED"})
+		e.appendRow([]interface{}{"POLICY " + name.String(), settings.String()})
+	}
+
+	return nil
+}
+
+func (e *ShowExec) fetchAllTablePlacements() error {
+	checker := privilege.GetPrivilegeManager(e.ctx)
+	activeRoles := e.ctx.GetSessionVars().ActiveRoles
+
+	dbs := e.is.AllSchemas()
+	sort.Slice(dbs, func(i, j int) bool { return dbs[i].Name.O < dbs[j].Name.O })
+
+	for _, dbInfo := range dbs {
+		tableRowSets := make([]struct {
+			name string
+			rows [][]interface{}
+		}, 0)
+
+		for _, tbl := range e.is.SchemaTables(dbInfo.Name) {
+			tblInfo := tbl.Meta()
+			if checker != nil && !checker.RequestVerification(activeRoles, dbInfo.Name.O, tblInfo.Name.O, "", mysql.AllPrivMask) {
+				continue
+			}
+
+			var rows [][]interface{}
+			ident := ast.Ident{Schema: dbInfo.Name, Name: tblInfo.Name}
+			placement, err := e.getTablePlacement(tblInfo)
+			if err != nil {
+				return err
+			}
+
+			if placement != nil {
+				rows = append(rows, []interface{}{"TABLE " + ident.String(), placement.String()})
+			}
+
+			// TODO: Add partition placement rules
+
+			if len(rows) > 0 {
+				tableRowSets = append(tableRowSets, struct {
+					name string
+					rows [][]interface{}
+				}{
+					name: tblInfo.Name.String(),
+					rows: rows,
+				})
+			}
+		}
+
+		sort.Slice(tableRowSets, func(i, j int) bool { return tableRowSets[i].name < tableRowSets[j].name })
+		for _, rowSet := range tableRowSets {
+			for _, row := range rowSet.rows {
+				e.appendRow(row)
+			}
+		}
 	}
 
 	return nil
 }
+
+func (e *ShowExec) getTablePlacement(tblInfo *model.TableInfo) (*model.PlacementSettings, error) {
+	placement := tblInfo.DirectPlacementOpts
+	if placement != nil {
+		return placement, nil
+	}
+
+	return e.getPolicyPlacement(tblInfo.PlacementPolicyRef)
+}
+
+func (e *ShowExec) getPolicyPlacement(policyRef *model.PolicyRefInfo) (settings *model.PlacementSettings, err error) {
+	if policyRef == nil {
+		return nil, nil
+	}
+
+	policy, ok := e.is.PolicyByName(policyRef.Name)
+	if !ok {
+		return nil, errors.Errorf("Policy with name '%s' not found", policyRef.Name)
+	}
+	return policy.PlacementSettings, nil
+}