add error code and fix some code style.

MariaDB · Sep 1, 2020 · 8a3d1f3 · 8a3d1f3
1 parent c32037c
commit 8a3d1f3
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Showing 4 changed files with 23 additions and 23 deletions.
diff --git a/mysql-test/main/merge.result b/mysql-test/main/merge.result
@@ -3038,7 +3038,6 @@ c1	c2
 411	421
 511	521
 #
-# MDEV-23485 - Change table to merge engine may cause table data lost.
 truncate table m1;
 ALTER TABLE m1 ENGINE=MRG_MyISAM UNION=(t1,t2)
 INSERT_METHOD=LAST;
@@ -3447,7 +3446,6 @@ c1	c2
 411	421
 511	521
 #
-# MDEV-23485 - Change table to merge engine may cause table data lost.
 truncate table m1;
 ALTER TABLE m1 ENGINE=MRG_MyISAM UNION=(t1,t2)
 INSERT_METHOD=LAST;
@@ -3924,13 +3922,13 @@ DROP TRIGGER trg1;
 DROP TABLE t1;
 DROP TABLE m1;
 #
-# MDEV-23485 - Change table to merge engine may cause table data lost. 
-# 
+# MDEV-23485 - Change table to merge engine may cause table data lost.
+#
 CREATE TABLE t1(a INT);
 ALTER TABLE t1 engine=MRG_MYISAM;
 drop table t1;
 CREATE TABLE t1(a INT);
 insert into t1() values(1);
 ALTER TABLE t1 engine=MRG_MYISAM;
-ERROR HY000: Storage engine MyISAM of the table `test`.`t1` doesn't have this option
+ERROR HY000: ALTER TABLE TO MERGE ENGINE is not supported for this operation, The original table is not merge engine and have rows may cause table data lost.
 drop table t1;
diff --git a/mysql-test/main/merge.test b/mysql-test/main/merge.test
@@ -2346,7 +2346,6 @@ INSERT INTO m1 VALUES (511, 521);
 SELECT * FROM m1;
 #
 --echo #
---echo # MDEV-23485 - Change table to merge engine may cause table data lost.
 truncate table m1;
 ALTER TABLE m1 ENGINE=MRG_MyISAM UNION=(t1,t2)
   INSERT_METHOD=LAST;
@@ -2514,7 +2513,6 @@ INSERT INTO m1 VALUES (511, 521);
 SELECT * FROM m1;
 #
 --echo #
---echo # MDEV-23485 - Change table to merge engine may cause table data lost.
 truncate table m1;
 ALTER TABLE m1 ENGINE=MRG_MyISAM UNION=(t1,t2)
   INSERT_METHOD=LAST;
@@ -2932,6 +2930,6 @@ ALTER TABLE t1 engine=MRG_MYISAM;
 drop table t1;
 CREATE TABLE t1(a INT);
 insert into t1() values(1);
---error ER_ILLEGAL_HA
+--error ER_ALTER_TO_MERGE_ENGINE_NOT_SUPPORTED
 ALTER TABLE t1 engine=MRG_MYISAM;
 drop table t1;
diff --git a/sql/share/errmsg-utf8.txt b/sql/share/errmsg-utf8.txt
@@ -7965,3 +7965,5 @@ ER_NOT_ALLOWED_IN_THIS_CONTEXT
         eng "'%-.128s' is not allowed in this context"
 ER_DATA_WAS_COMMITED_UNDER_ROLLBACK
         eng "Engine %s does not support rollback. Changes where committed during rollback call"
+ER_ALTER_TO_MERGE_ENGINE_NOT_SUPPORTED
+        eng "%s is not supported for this operation, The original table is not merge engine and have rows may cause table data lost."
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
@@ -10130,31 +10130,33 @@ bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
     DBUG_RETURN(true);
   }
 
-  /* MDEV-23485: Change table to merge engine may cause table data lost.
-   * If we want to change a table to merge engine, the original table
-   * should't be merge engine table and the table have no rows, otherwise
-   * may cause table data lost. */
+  /*
+    MDEV-23485: Change table to merge engine may cause table data lost.
+
+    If we want to change a table to merge engine, the original table
+    should't be merge engine table and the table have no rows, otherwise
+    may cause table data lost.
+  */
   if (table->file->ht->db_type != DB_TYPE_MRG_MYISAM &&
-      create_info->db_type->db_type == DB_TYPE_MRG_MYISAM) {
+      create_info->db_type->db_type == DB_TYPE_MRG_MYISAM)
+  {
     READ_RECORD info;
-    bool have_rows= false;
-    if (init_read_record(&info, thd, table, NULL, NULL, 1, 1, FALSE)) {
+    if (init_read_record(&info, thd, table, NULL, NULL, 1, 1, FALSE))
+    {
       DBUG_RETURN(true);
     }
 
-    while (likely(!(error= info.read_record())))
+    while (!(error= info.read_record()))
     {
-      have_rows= true;
-      break;
-    }
-
-    if (have_rows) {
       DBUG_PRINT("info", ("The original table is not merge table "
                           "and have rows doesn't support alter"));
-      my_error(ER_ILLEGAL_HA, MYF(0), hton_name(table->s->db_type())->str,
-               alter_ctx.db.str, alter_ctx.table_name.str);
+      my_error(ER_ALTER_TO_MERGE_ENGINE_NOT_SUPPORTED, MYF(0),
+              "ALTER TABLE TO MERGE ENGINE");
+      end_read_record(&info);
       DBUG_RETURN(true);
     }
+
+    end_read_record(&info);
   }
 
   if (table->s->tmp_table == NO_TMP_TABLE)