admin: fix admin check table compare bug (pingcap#7818)

executor/admin_test.go

@@ -498,6 +498,14 @@ func (s *testSuite) TestAdminCheckTable(c *C) {
  tk.MustExec(`ALTER TABLE t1 ADD INDEX idx5 (c5)`)
  tk.MustExec(`ALTER TABLE t1 ADD INDEX idx6 (c6)`)
  tk.MustExec(`admin check table t1`)
+
+ // Test add index on decimal column.
+ tk.MustExec(`drop table if exists td1;`)
+ tk.MustExec(`CREATE TABLE td1 (c2 INT NULL DEFAULT '70');`)
+ tk.MustExec(`INSERT INTO td1 SET c2 = '5';`)
+ tk.MustExec(`ALTER TABLE td1 ADD COLUMN c4 DECIMAL(12,8) NULL DEFAULT '213.41598062';`)
+ tk.MustExec(`ALTER TABLE td1 ADD INDEX id2 (c4) ;`)
+ tk.MustExec(`ADMIN CHECK TABLE td1;`)
 }
 
 func (s *testSuite) TestAdminCheckPrimaryIndex(c *C) {

util/admin/admin.go

@@ -353,6 +353,7 @@ func checkIndexAndRecord(sessCtx sessionctx.Context, txn kv.Transaction, t table
  if err != nil {
  return errors.Trace(err)
  }
+ sc := new(stmtctx.StatementContext)
  for {
  vals1, h, err := it.Next()
  if terror.ErrorEqual(err, io.EOF) {
@@ -375,7 +376,7 @@ func checkIndexAndRecord(sessCtx sessionctx.Context, txn kv.Transaction, t table
  return errors.Trace(err)
  }
  adjustDatumKind(vals1, vals2)
- if !reflect.DeepEqual(vals1, vals2) {
+ if !compareDatumSlice(sc, vals1, vals2) {
  record1 := &RecordData{Handle: h, Values: vals1}
  record2 := &RecordData{Handle: h, Values: vals2}
  return ErrDataInConsistent.GenWithStack("index:%#v != record:%#v", record1, record2)
@@ -385,6 +386,25 @@ func checkIndexAndRecord(sessCtx sessionctx.Context, txn kv.Transaction, t table
  return nil
 }
 
+func compareDatumSlice(sc *stmtctx.StatementContext, val1s, val2s []types.Datum) bool {
+ if len(val1s) != len(val2s) {
+ return false
+ }
+ for i, v := range val1s {
+ if v.Kind() == types.KindMysqlDecimal {
+ res, err := v.CompareDatum(sc, &val2s[i])
+ if err != nil || res != 0 {
+ return false
+ }
+ } else {
+ if !reflect.DeepEqual(v, val2s[i]) {
+ return false
+ }
+ }
+ }
+ return true
+}
+
 // CheckRecordAndIndex is exported for testing.
 func CheckRecordAndIndex(sessCtx sessionctx.Context, txn kv.Transaction, t table.Table, idx table.Index, genExprs map[string]expression.Expression) error {
  sc := sessCtx.GetSessionVars().StmtCtx