ddl: add admin check before drop table using building flag. (#7343)

Makefile

@@ -34,12 +34,18 @@ LDFLAGS += -X "github.com/pingcap/tidb/util/printer.TiDBGitHash=$(shell git rev-
 LDFLAGS += -X "github.com/pingcap/tidb/util/printer.TiDBGitBranch=$(shell git rev-parse --abbrev-ref HEAD)"
 LDFLAGS += -X "github.com/pingcap/tidb/util/printer.GoVersion=$(shell go version)"
 
+TEST_LDFLAGS =  -X "github.com/pingcap/tidb/config.checkBeforeDropLDFlag=1"
+
+CHECK_LDFLAGS += $(LDFLAGS) ${TEST_LDFLAGS}
+
 TARGET = ""
 
 .PHONY: all build update parser clean todo test gotest interpreter server dev benchkv benchraw check parserlib checklist
 
 default: server buildsucc
 
+server-admin-check: server_check buildsucc
+
 buildsucc:
 	@echo Build TiDB Server successfully!
 
@@ -141,7 +147,7 @@ ifeq ("$(TRAVIS_COVERAGE)", "1")
 else
 	@echo "Running in native mode."
 	@export log_level=error; \
-	$(GOTEST) -cover $(PACKAGES) || { $(GOFAIL_DISABLE); exit 1; }
+	$(GOTEST) -ldflags '$(TEST_LDFLAGS)' -cover $(PACKAGES) || { $(GOFAIL_DISABLE); exit 1; }
 endif
 	@$(GOFAIL_DISABLE)
 
@@ -178,6 +184,13 @@ else
 	$(GOBUILD) $(RACE_FLAG) -ldflags '$(LDFLAGS)' -o '$(TARGET)' tidb-server/main.go
 endif
 
+server_check: parserlib
+ifeq ($(TARGET), "")
+	$(GOBUILD) $(RACE_FLAG) -ldflags '$(CHECK_LDFLAGS)' -o bin/tidb-server tidb-server/main.go
+else
+	$(GOBUILD) $(RACE_FLAG) -ldflags '$(CHECK_LDFLAGS)' -o '$(TARGET)' tidb-server/main.go
+endif
+
 benchkv:
 	$(GOBUILD) -ldflags '$(LDFLAGS)' -o bin/benchkv cmd/benchkv/main.go
 

config/config.go

@@ -36,6 +36,10 @@ var (
 		"mocktikv": true,
 		"tikv":     true,
 	}
+	// checkTableBeforeDrop enable to execute `admin check table` before `drop table`.
+	CheckTableBeforeDrop = false
+	// checkBeforeDropLDFlag is a go build flag.
+	checkBeforeDropLDFlag = "None"
 )
 
 // Config contains configuration options.
@@ -374,6 +378,12 @@ func (t *OpenTracing) ToTracingConfig() *tracing.Configuration {
 	return ret
 }
 
+func init() {
+	if checkBeforeDropLDFlag == "1" {
+		CheckTableBeforeDrop = true
+	}
+}
+
 // The following constants represents the valid action configurations for OOMAction.
 // NOTE: Althrough the values is case insensitiv, we should use lower-case
 // strings because the configuration value will be transformed to lower-case

executor/admin_test.go

@@ -471,6 +471,11 @@ func (s *testSuite) TestAdminCheckTable(c *C) {
   			INDEX indexIDname (ID(8),name(8)));`)
 	tk.MustExec(`INSERT INTO t VALUES ('keyword','urlprefix','text/ /text');`)
 	tk.MustExec(`admin check table t;`)
+
+	tk.MustExec("use mysql")
+	tk.MustExec(`admin check table test.t;`)
+	_, err := tk.Exec("admin check table t")
+	c.Assert(err, NotNil)
 }
 
 func (s *testSuite) TestAdminCheckPrimaryIndex(c *C) {

executor/ddl.go

@@ -14,17 +14,21 @@
 package executor
 
 import (
+	"fmt"
 	"strings"
 
 	"github.com/juju/errors"
 	"github.com/pingcap/tidb/ast"
+	"github.com/pingcap/tidb/config"
 	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/model"
 	"github.com/pingcap/tidb/mysql"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/types"
 	"github.com/pingcap/tidb/util/chunk"
+	"github.com/pingcap/tidb/util/sqlexec"
+	log "github.com/sirupsen/logrus"
 	"golang.org/x/net/context"
 )
 
@@ -194,6 +198,15 @@ func (e *DDLExec) executeDropTable(s *ast.DropTableStmt) error {
 			return errors.Trace(err)
 		}
 
+		if config.CheckTableBeforeDrop {
+			log.Warnf("admin check table `%s`.`%s` before drop.", fullti.Schema.O, fullti.Name.O)
+			sql := fmt.Sprintf("admin check table `%s`.`%s`", fullti.Schema.O, fullti.Name.O)
+			_, _, err = e.ctx.(sqlexec.RestrictedSQLExecutor).ExecRestrictedSQL(e.ctx, sql)
+			if err != nil {
+				return errors.Trace(err)
+			}
+		}
+
 		err = domain.GetDomain(e.ctx).DDL().DropTable(e.ctx, fullti)
 		if infoschema.ErrDatabaseNotExists.Equal(err) || infoschema.ErrTableNotExists.Equal(err) {
 			notExistTables = append(notExistTables, fullti.String())

executor/executor.go

@@ -369,8 +369,8 @@ func (e *CheckTableExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 		return nil
 	}
 	defer func() { e.done = true }()
-	dbName := model.NewCIStr(e.ctx.GetSessionVars().CurrentDB)
 	for _, t := range e.tables {
+		dbName := t.DBInfo.Name
 		tb, err := e.is.TableByName(dbName, t.Name)
 		if err != nil {
 			return errors.Trace(err)

executor/executor_test.go

@@ -233,9 +233,17 @@ func (s *testSuite) TestAdmin(c *C) {
 	c.Assert(err, IsNil)
 	err = txn.Commit(context.Background())
 	c.Assert(err, IsNil)
-	r, err = tk.Exec("admin check table admin_test")
-	c.Assert(err, NotNil)
+	r, err_admin := tk.Exec("admin check table admin_test")
+	c.Assert(err_admin, NotNil)
+
+	if config.CheckTableBeforeDrop {
+		r, err = tk.Exec("drop table admin_test")
+		c.Assert(err.Error(), Equals, err_admin.Error())
 
+		// Drop inconsistency index.
+		tk.MustExec("alter table admin_test drop index c1")
+		tk.MustExec("admin check table admin_test")
+	}
 	// checksum table test
 	tk.MustExec("create table checksum_with_index (id int, count int, PRIMARY KEY(id), KEY(count))")
 	tk.MustExec("create table checksum_without_index (id int, count int, PRIMARY KEY(id))")

util/printer/printer.go

@@ -43,6 +43,7 @@ func PrintTiDBInfo() {
 	log.Infof("UTC Build Time:  %s", TiDBBuildTS)
 	log.Infof("GoVersion:  %s", GoVersion)
 	log.Infof("Race Enabled: %v", israce.RaceEnabled)
+	log.Infof("Check Table Before Drop: %v", config.CheckTableBeforeDrop)
 	log.Infof("TiKV Min Version: %s", TiKVMinVersion)
 	configJSON, err := json.Marshal(config.GetGlobalConfig())
 	if err != nil {