infoschema: Support for showing "AUTO_INCREMENT" in "information_sche…

…ma.tables" (#7037)
pingcap · Jul 14, 2018 · 419e5cf · 419e5cf
1 parent c1b4490
commit 419e5cf
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Showing 2 changed files with 37 additions and 1 deletion.
diff --git a/infoschema/tables.go b/infoschema/tables.go
@@ -651,6 +651,29 @@ func getRowCountAllTable(ctx sessionctx.Context) (map[int64]uint64, error) {
 	return rowCountMap, nil
 }
 
+func getAutoIncrementID(ctx sessionctx.Context, schema *model.DBInfo, tblInfo *model.TableInfo) (int64, error) {
+	hasAutoIncID := false
+	for _, col := range tblInfo.Cols() {
+		if mysql.HasAutoIncrementFlag(col.Flag) {
+			hasAutoIncID = true
+			break
+		}
+	}
+	autoIncID := tblInfo.AutoIncID
+	if hasAutoIncID {
+		is := ctx.GetSessionVars().TxnCtx.InfoSchema.(InfoSchema)
+		tbl, err := is.TableByName(schema.Name, tblInfo.Name)
+		if err != nil {
+			return 0, errors.Trace(err)
+		}
+		autoIncID, err = tbl.Allocator(ctx).NextGlobalAutoID(tblInfo.ID)
+		if err != nil {
+			return 0, errors.Trace(err)
+		}
+	}
+	return autoIncID, nil
+}
+
 func dataForTables(ctx sessionctx.Context, schemas []*model.DBInfo) ([][]types.Datum, error) {
 	tableRowsMap, err := getRowCountAllTable(ctx)
 	if err != nil {
@@ -676,6 +699,10 @@ func dataForTables(ctx sessionctx.Context, schemas []*model.DBInfo) ([][]types.D
 				continue
 			}
 
+			autoIncID, err := getAutoIncrementID(ctx, schema, table)
+			if err != nil {
+				return nil, errors.Trace(err)
+			}
 			record := types.MakeDatums(
 				catalogVal,             // TABLE_CATALOG
 				schema.Name.O,          // TABLE_SCHEMA
@@ -690,7 +717,7 @@ func dataForTables(ctx sessionctx.Context, schemas []*model.DBInfo) ([][]types.D
 				uint64(0),              // MAX_DATA_LENGTH
 				uint64(0),              // INDEX_LENGTH
 				uint64(0),              // DATA_FREE
-				table.AutoIncID,        // AUTO_INCREMENT
+				autoIncID,              // AUTO_INCREMENT
 				createTime,             // CREATE_TIME
 				nil,                    // UPDATE_TIME
 				nil,                    // CHECK_TIME

diff --git a/infoschema/tables_test.go b/infoschema/tables_test.go
@@ -65,6 +65,15 @@ func (s *testSuite) TestDataForTableRowsCountField(c *C) {
 	tk.MustQuery("select table_rows from information_schema.tables where table_name='t'").Check(
 		testkit.Rows("2"))
 
+	// Test for auto increment ID.
+	tk.MustExec("drop table t")
+	tk.MustExec("create table t (c int auto_increment primary key, d int)")
+	tk.MustQuery("select auto_increment from information_schema.tables where table_name='t'").Check(
+		testkit.Rows("1"))
+	tk.MustExec("insert into t(c, d) values(1, 1)")
+	tk.MustQuery("select auto_increment from information_schema.tables where table_name='t'").Check(
+		testkit.Rows("30002"))
+
 	tk.MustExec("create user xxx")
 	tk.MustExec("flush privileges")