SQL: prohibit ALTER ... AS ROW START|END [fixes #429]

mysql-test/suite/versioning/r/alter.result

@@ -429,8 +429,8 @@ alter table t1 engine=myisam;
 # MDEV-14692 crash in MDL_context::upgrade_shared_lock()
 create or replace temporary table t (a int);
 alter table t change column if exists b c bigint unsigned generated always as row start;
-ERROR HY000: GENERATED AS ROW START prohibited for TEMPORARY tables
+ERROR HY000: This is not yet supported for generated columns
 alter table t change column if exists b c bigint unsigned generated always as row end;
-ERROR HY000: GENERATED AS ROW END prohibited for TEMPORARY tables
+ERROR HY000: This is not yet supported for generated columns
 drop database test;
 create database test;

mysql-test/suite/versioning/r/insert.result

@@ -290,7 +290,7 @@ insert into t1(x) values (1);
 ERROR HY000: Temporal operation requires `mysql.transaction_registry` (@@system_versioning_transaction_registry).
 set global system_versioning_transaction_registry= on;
 Warnings:
-Warning	4144	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
+Warning	4143	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
 create or replace table t1 (
 x int,
 y int as (x) virtual,

mysql-test/suite/versioning/r/online.result

@@ -14,7 +14,7 @@ alter table t drop system versioning, algorithm=inplace;
 ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: Not implemented for system-versioned tables. Try ALGORITHM=COPY
 set global system_versioning_transaction_registry=on;
 Warnings:
-Warning	4144	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
+Warning	4143	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
 create or replace table t (a int, b int) engine=innodb;
 alter table t
 add s bigint unsigned as row start,

mysql-test/suite/versioning/r/trx_id.result

@@ -10,7 +10,7 @@ period for system_time (sys_trx_start, sys_trx_end)
 ERROR HY000: Temporal operation requires `mysql.transaction_registry` (@@system_versioning_transaction_registry).
 set global system_versioning_transaction_registry= 1;
 Warnings:
-Warning	4144	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
+Warning	4143	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
 create or replace table t1 (
 x int,
 sys_trx_start bigint(20) unsigned as row start invisible,
@@ -32,7 +32,7 @@ return if(cond = 1, '[CORRECT]', '[INCORRECT]');
 set @@system_versioning_alter_history=keep;
 set global system_versioning_transaction_registry=on;
 Warnings:
-Warning	4144	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
+Warning	4143	Transaction-based system versioning is EXPERIMENTAL and is subject to change in future.
 create or replace table t1 (x int) engine innodb;
 insert into t1 values (1);
 alter table t1

mysql-test/suite/versioning/t/alter.test

@@ -316,10 +316,10 @@ create or replace table non_empty (
 ) engine innodb;
 insert into non_empty values (1, 100, 200);
 
---error ER_VERS_GENERATED_ALWAYS_NOT_EMPTY
+--error ER_UNSUPPORTED_ACTION_ON_GENERATED_COLUMN
 alter table non_empty
   change column sys_trx_start sys_trx_start bigint(20) unsigned as row start invisible;
---error ER_VERS_GENERATED_ALWAYS_NOT_EMPTY
+--error ER_UNSUPPORTED_ACTION_ON_GENERATED_COLUMN
 alter table non_empty
   change column sys_trx_end sys_trx_end bigint(20) unsigned as row end invisible;
 drop table non_empty;
@@ -364,9 +364,9 @@ alter table t1 engine=myisam;
 
 --echo # MDEV-14692 crash in MDL_context::upgrade_shared_lock()
 create or replace temporary table t (a int);
---error ER_VERS_TEMPORARY
+--error ER_UNSUPPORTED_ACTION_ON_GENERATED_COLUMN
 alter table t change column if exists b c bigint unsigned generated always as row start;
---error ER_VERS_TEMPORARY
+--error ER_UNSUPPORTED_ACTION_ON_GENERATED_COLUMN
 alter table t change column if exists b c bigint unsigned generated always as row end;
 
 

sql/handler.cc

@@ -7295,31 +7295,14 @@ bool Vers_parse_info::fix_alter_info(THD *thd, Alter_info *alter_info,
     return false;
   }
 
-  if (!share->versioned)
   {
     List_iterator_fast<Create_field> it(alter_info->create_list);
     while (Create_field *f= it++)
     {
       if (f->change.length && f->flags & VERS_SYSTEM_FIELD)
       {
-        if (share->table_category == TABLE_CATEGORY_TEMPORARY) {
-          my_error(ER_VERS_TEMPORARY, MYF(0),
-                   f->flags & VERS_SYS_START_FLAG ? "GENERATED AS ROW START"
-                                                  : "GENERATED AS ROW END");
-          return true;
-        }
-        if (thd->mdl_context.upgrade_shared_lock(
-                table->mdl_ticket, MDL_EXCLUSIVE,
-                thd->variables.lock_wait_timeout))
-          return true;
-        if (table->file->info(HA_STATUS_VARIABLE | HA_STATUS_TIME))
+        my_error(ER_UNSUPPORTED_ACTION_ON_GENERATED_COLUMN, MYF(0));
         return true;
-        if (0 < table->file->records())
-        {
-          my_error(ER_VERS_GENERATED_ALWAYS_NOT_EMPTY, MYF(0), f->change.str);
-          return true;
-        }
-        break;
       }
     }
   }

sql/share/errmsg-utf8.txt

@@ -7915,9 +7915,6 @@ ER_VERS_SYS_FIELD_NOT_HIDDEN
 ER_NOT_LOG_TABLE
         eng "Table %`s.%`s is not a log table"
 
-ER_VERS_GENERATED_ALWAYS_NOT_EMPTY
-        eng "Can not modify column %`s to GENERATED ALWAYS AS ROW START/END for non-empty table"
-
 ER_VERS_TRT_IS_DISABLED
         eng "Temporal operation requires `mysql.transaction_registry` (@@system_versioning_transaction_registry)."