*: support for "admin show next_row_id" (#8268)

ast/misc.go

@@ -595,6 +595,8 @@ const (
 	AdminCheckIndexRange
 	AdminShowDDLJobQueries
 	AdminChecksumTable
+	AdminShowSlow
+	AdminShowNextRowID
 )
 
 // HandleRange represents a range where handle value >= Begin and < End.

executor/admin_test.go

@@ -15,6 +15,7 @@ package executor_test
 
 import (
 	. "github.com/pingcap/check"
+	"github.com/pingcap/tidb/meta/autoid"
 	"github.com/pingcap/tidb/model"
 	"github.com/pingcap/tidb/table/tables"
 	"github.com/pingcap/tidb/types"
@@ -458,3 +459,45 @@ func (s *testSuite) TestAdminCheckTable(c *C) {
 	tk.MustExec(`ALTER TABLE t1 ADD INDEX idx6 (c6)`)
 	tk.MustExec(`admin check table t1`)
 }
+
+func (s *testSuite) TestAdminShowNextID(c *C) {
+	step := int64(10)
+	autoIDStep := autoid.GetStep()
+	autoid.SetStep(step)
+	defer autoid.SetStep(autoIDStep)
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("create table t(id int, c int)")
+	// Start handle is 1.
+	r := tk.MustQuery("admin show t next_row_id")
+	r.Check(testkit.Rows("test t _tidb_rowid 1"))
+	// Row ID is step + 1.
+	tk.MustExec("insert into t values(1, 1)")
+	r = tk.MustQuery("admin show t next_row_id")
+	r.Check(testkit.Rows("test t _tidb_rowid 11"))
+	// Row ID is original + step.
+	for i := 0; i < int(step); i++ {
+		tk.MustExec("insert into t values(10000, 1)")
+	}
+	r = tk.MustQuery("admin show t next_row_id")
+	r.Check(testkit.Rows("test t _tidb_rowid 21"))
+
+	// test for a table with the primary key
+	tk.MustExec("create table tt(id int primary key auto_increment, c int)")
+	// Start handle is 1.
+	r = tk.MustQuery("admin show tt next_row_id")
+	r.Check(testkit.Rows("test tt id 1"))
+	// After rebasing auto ID, row ID is 20 + step + 1.
+	tk.MustExec("insert into tt values(20, 1)")
+	r = tk.MustQuery("admin show tt next_row_id")
+	r.Check(testkit.Rows("test tt id 31"))
+	// test for renaming the table
+	tk.MustExec("create database test1")
+	tk.MustExec("rename table test.tt to test1.tt")
+	tk.MustExec("use test1")
+	r = tk.MustQuery("admin show tt next_row_id")
+	r.Check(testkit.Rows("test1 tt id 31"))
+	tk.MustExec("insert test1.tt values ()")
+	r = tk.MustQuery("admin show tt next_row_id")
+	r.Check(testkit.Rows("test1 tt id 41"))
+}

executor/aggregate_test.go

@@ -239,8 +239,8 @@ func (s *testSuite) TestAggregation(c *C) {
 	result.Check(testkit.Rows("<nil>", "<nil>"))
 
 	result = tk.MustQuery("select count(*) from information_schema.columns")
-	// When adding new memory columns in information_schema, please update this variable.\
-	columnCountOfAllInformationSchemaTables := "754"
+	// When adding new memory columns in information_schema, please update this variable.
+	columnCountOfAllInformationSchemaTables := "756"
 	result.Check(testkit.Rows(columnCountOfAllInformationSchemaTables))
 
 	tk.MustExec("drop table if exists t1")

executor/builder.go

@@ -104,6 +104,8 @@ func (b *executorBuilder) build(p plan.Plan) Executor {
 		return b.buildSelectLock(v)
 	case *plan.CancelDDLJobs:
 		return b.buildCancelDDLJobs(v)
+	case *plan.ShowNextRowID:
+		return b.buildShowNextRowID(v)
 	case *plan.ShowDDL:
 		return b.buildShowDDL(v)
 	case *plan.ShowDDLJobs:
@@ -177,6 +179,14 @@ func (b *executorBuilder) buildCancelDDLJobs(v *plan.CancelDDLJobs) Executor {
 	return e
 }
 
+func (b *executorBuilder) buildShowNextRowID(v *plan.ShowNextRowID) Executor {
+	e := &ShowNextRowIDExec{
+		baseExecutor: newBaseExecutor(b.ctx, v.Schema(), v.ExplainID()),
+		tblName:      v.TableName,
+	}
+	return e
+}
+
 func (b *executorBuilder) buildShowDDL(v *plan.ShowDDL) Executor {
 	// We get DDLInfo here because for Executors that returns result set,
 	// next will be called after transaction has been committed.

executor/executor.go

@@ -22,6 +22,7 @@ import (
 	"github.com/cznic/mathutil"
 	"github.com/juju/errors"
 	"github.com/pingcap/tidb/ast"
+	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/expression"
 	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/kv"
@@ -49,6 +50,7 @@ var (
 	_ Executor = &ProjectionExec{}
 	_ Executor = &SelectionExec{}
 	_ Executor = &SelectLockExec{}
+	_ Executor = &ShowNextRowIDExec{}
 	_ Executor = &ShowDDLExec{}
 	_ Executor = &ShowDDLJobsExec{}
 	_ Executor = &ShowDDLJobQueriesExec{}
@@ -221,6 +223,43 @@ func (e *CancelDDLJobsExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	return nil
 }
 
+// ShowNextRowIDExec represents a show the next row ID executor.
+type ShowNextRowIDExec struct {
+	baseExecutor
+	tblName *ast.TableName
+	done    bool
+}
+
+// Next implements the Executor Next interface.
+func (e *ShowNextRowIDExec) Next(ctx context.Context, chk *chunk.Chunk) error {
+	chk.Reset()
+	if e.done {
+		return nil
+	}
+	is := domain.GetDomain(e.ctx).InfoSchema()
+	tbl, err := is.TableByName(e.tblName.Schema, e.tblName.Name)
+	if err != nil {
+		return errors.Trace(err)
+	}
+	colName := model.ExtraHandleName
+	for _, col := range tbl.Meta().Columns {
+		if mysql.HasAutoIncrementFlag(col.Flag) {
+			colName = col.Name
+			break
+		}
+	}
+	nextGlobalID, err := tbl.Allocator(e.ctx).NextGlobalAutoID(tbl.Meta().ID)
+	if err != nil {
+		return errors.Trace(err)
+	}
+	chk.AppendString(0, e.tblName.Schema.O)
+	chk.AppendString(1, e.tblName.Name.O)
+	chk.AppendString(2, colName.O)
+	chk.AppendInt64(3, nextGlobalID)
+	e.done = true
+	return nil
+}
+
 // ShowDDLExec represents a show DDL executor.
 type ShowDDLExec struct {
 	baseExecutor

parser/misc.go

@@ -352,6 +352,7 @@ var tokenMap = map[string]int{
 	"NAMES":                    names,
 	"NATIONAL":                 national,
 	"NATURAL":                  natural,
+	"NEXT_ROW_ID":              nextRowID,
 	"NO":                       no,
 	"NO_WRITE_TO_BINLOG":       noWriteToBinLog,
 	"NONE":                     none,

parser/parser.y

@@ -396,30 +396,31 @@ import (
 	yearType	"YEAR"
 
 	/* The following tokens belong to NotKeywordToken. */
-	addDate		"ADDDATE"
-	bitAnd		"BIT_AND"
-	bitOr		"BIT_OR"
-	bitXor		"BIT_XOR"
-	cast		"CAST"
-	copyKwd		"COPY"
-	count		"COUNT"
-	curTime		"CURTIME"
-	dateAdd		"DATE_ADD"
-	dateSub		"DATE_SUB"
-	extract		"EXTRACT"
-	getFormat	"GET_FORMAT"
-	groupConcat	"GROUP_CONCAT"
-	inplace 	"INPLACE"
-	min		"MIN"
-	max		"MAX"
-	now		"NOW"
-	position	"POSITION"
-	subDate		"SUBDATE"
-	sum		"SUM"
-	substring	"SUBSTRING"
-	timestampAdd	"TIMESTAMPADD"
-	timestampDiff	"TIMESTAMPDIFF"
-	trim		"TRIM"
+	addDate			"ADDDATE"
+	bitAnd			"BIT_AND"
+	bitOr			"BIT_OR"
+	bitXor			"BIT_XOR"
+	cast			"CAST"
+	copyKwd			"COPY"
+	count			"COUNT"
+	curTime			"CURTIME"
+	dateAdd			"DATE_ADD"
+	dateSub			"DATE_SUB"
+	extract			"EXTRACT"
+	getFormat		"GET_FORMAT"
+	groupConcat		"GROUP_CONCAT"
+	nextRowID		"NEXT_ROW_ID"
+	inplace 		"INPLACE"
+	min			"MIN"
+	max			"MAX"
+	now			"NOW"
+	position		"POSITION"
+	subDate			"SUBDATE"
+	sum			"SUM"
+	substring		"SUBSTRING"
+	timestampAdd		"TIMESTAMPADD"
+	timestampDiff		"TIMESTAMPDIFF"
+	trim			"TRIM"
 
 	/* The following tokens belong to TiDBKeyword. */
 	admin		"ADMIN"
@@ -2629,7 +2630,7 @@ TiDBKeyword:
 
 NotKeywordToken:
  "ADDDATE" | "BIT_AND" | "BIT_OR" | "BIT_XOR" | "CAST" | "COPY" | "COUNT" | "CURTIME" | "DATE_ADD" | "DATE_SUB" | "EXTRACT" | "GET_FORMAT" | "GROUP_CONCAT" 
-| "INPLACE" |"MIN" | "MAX" | "NOW" | "POSITION" | "SUBDATE" | "SUBSTRING" | "SUM" | "TIMESTAMPADD" | "TIMESTAMPDIFF" | "TRIM"
+| "INPLACE" |"MIN" | "MAX" | "NOW" | "POSITION" | "SUBDATE" | "SUBSTRING" | "SUM" | "TIMESTAMPADD" | "TIMESTAMPDIFF" | "TRIM" | "NEXT_ROW_ID"
 
 /************************************************************************************
  *
@@ -4924,6 +4925,13 @@ AdminStmt:
 	{
 		$$ = &ast.AdminStmt{Tp: ast.AdminShowDDLJobs}
 	}
+|	"ADMIN" "SHOW" TableName "NEXT_ROW_ID"
+	{
+		$$ = &ast.AdminStmt{
+			Tp: ast.AdminShowNextRowID,
+			Tables: []*ast.TableName{$3.(*ast.TableName)},
+		}
+	}
 |	"ADMIN" "CHECK" "TABLE" TableNameList
 	{
 		$$ = &ast.AdminStmt{

parser/parser_test.go

@@ -422,6 +422,7 @@ func (s *testParserSuite) TestDMLStmt(c *C) {
 		{"admin checksum table t1, t2;", true},
 		{"admin cancel ddl jobs 1", true},
 		{"admin cancel ddl jobs 1, 2", true},
+		{"admin show t1 next_row_id", true},
 		{"admin recover index t1 idx_a", true},
 		{"admin cleanup index t1 idx_a", true},
 

plan/common_plans.go

@@ -50,6 +50,12 @@ type ShowDDLJobQueries struct {
 	JobIDs []int64
 }
 
+// ShowNextRowID is for showing the next global row ID.
+type ShowNextRowID struct {
+	baseSchemaProducer
+	TableName *ast.TableName
+}
+
 // CheckTable is used for checking table data, built from the 'admin check table' statement.
 type CheckTable struct {
 	baseSchemaProducer

plan/planbuilder.go

@@ -475,6 +475,10 @@ func (b *planBuilder) buildAdmin(as *ast.AdminStmt) Plan {
 		p := &ChecksumTable{Tables: as.Tables}
 		p.SetSchema(buildChecksumTableSchema())
 		ret = p
+	case ast.AdminShowNextRowID:
+		p := &ShowNextRowID{TableName: as.Tables[0]}
+		p.SetSchema(buildShowNextRowID())
+		ret = p
 	case ast.AdminShowDDL:
 		p := &ShowDDL{}
 		p.SetSchema(buildShowDDLFields())
@@ -628,6 +632,15 @@ func (b *planBuilder) buildAnalyze(as *ast.AnalyzeTableStmt) Plan {
 	return b.buildAnalyzeTable(as)
 }
 
+func buildShowNextRowID() *expression.Schema {
+	schema := expression.NewSchema(make([]*expression.Column, 0, 4)...)
+	schema.Append(buildColumn("", "DB_NAME", mysql.TypeVarchar, mysql.MaxDatabaseNameLength))
+	schema.Append(buildColumn("", "TABLE_NAME", mysql.TypeVarchar, mysql.MaxTableNameLength))
+	schema.Append(buildColumn("", "COLUMN_NAME", mysql.TypeVarchar, mysql.MaxColumnNameLength))
+	schema.Append(buildColumn("", "NEXT_GLOBAL_ROW_ID", mysql.TypeLonglong, 4))
+	return schema
+}
+
 func buildShowDDLFields() *expression.Schema {
 	schema := expression.NewSchema(make([]*expression.Column, 0, 4)...)
 	schema.Append(buildColumn("", "SCHEMA_VER", mysql.TypeLonglong, 4))