SQL: don't update TRT when altered [#305, #302]

Tests affected: main.mysqlcheck

mysql-test/r/mysqlcheck.result

@@ -31,6 +31,7 @@ mysql.time_zone_leap_second                        OK
 mysql.time_zone_name                               OK
 mysql.time_zone_transition                         OK
 mysql.time_zone_transition_type                    OK
+mysql.transaction_registry                         OK
 mysql.user                                         OK
 mysql.vtmd_template                                OK
 mtr.global_suppressions                            Table is already up to date
@@ -66,6 +67,9 @@ mysql.time_zone_leap_second                        OK
 mysql.time_zone_name                               OK
 mysql.time_zone_transition                         OK
 mysql.time_zone_transition_type                    OK
+mysql.transaction_registry
+note     : Table does not support optimize, doing recreate + analyze instead
+status   : OK
 mysql.user                                         OK
 mysql.vtmd_template
 note     : Table does not support optimize, doing recreate + analyze instead
@@ -97,6 +101,7 @@ mysql.time_zone_leap_second                        OK
 mysql.time_zone_name                               OK
 mysql.time_zone_transition                         OK
 mysql.time_zone_transition_type                    OK
+mysql.transaction_registry                         OK
 mysql.user                                         OK
 mysql.vtmd_template                                OK
 mysql.column_stats                                 Table is already up to date
@@ -130,6 +135,9 @@ mysql.time_zone_leap_second                        Table is already up to date
 mysql.time_zone_name                               Table is already up to date
 mysql.time_zone_transition                         Table is already up to date
 mysql.time_zone_transition_type                    Table is already up to date
+mysql.transaction_registry
+note     : Table does not support optimize, doing recreate + analyze instead
+status   : OK
 mysql.user                                         Table is already up to date
 mysql.vtmd_template
 note     : Table does not support optimize, doing recreate + analyze instead
@@ -455,6 +463,7 @@ mysql.time_zone_leap_second                        Table is already up to date
 mysql.time_zone_name                               Table is already up to date
 mysql.time_zone_transition                         Table is already up to date
 mysql.time_zone_transition_type                    Table is already up to date
+mysql.transaction_registry                         OK
 mysql.user                                         Table is already up to date
 mysql.vtmd_template                                OK
 mysqltest1.t1

sql/sql_table.cc

@@ -7430,7 +7430,7 @@ static bool mysql_inplace_alter_table(THD *thd,
 
   {
     TR_table trt(thd, true);
-    if (table->file->native_versioned())
+    if (table->file->native_versioned() && trt != *table_list)
     {
       if (opt_transaction_registry && trt.update())
         return true;

sql/table.h

@@ -2961,6 +2961,15 @@ class TR_table: public TABLE_LIST
                   ulonglong commit_id1= 0, enum_tx_isolation iso_level1= ISO_READ_UNCOMMITTED,
                   ulonglong commit_id0= 0);
 
+  enum_tx_isolation iso_level() const;
+  void store_iso_level(enum_tx_isolation iso_level)
+  {
+    DBUG_ASSERT(iso_level <= ISO_SERIALIZABLE);
+    store(FLD_ISO_LEVEL, iso_level + 1);
+  }
+  bool check();
+
+public:
   TABLE * operator-> () const
   {
     return table;
@@ -2974,13 +2983,16 @@ class TR_table: public TABLE_LIST
   {
     return table;
   }
-  enum_tx_isolation iso_level() const;
-  void store_iso_level(enum_tx_isolation iso_level)
+  bool operator== (TABLE_LIST &subj) const
   {
-    DBUG_ASSERT(iso_level <= ISO_SERIALIZABLE);
-    store(FLD_ISO_LEVEL, iso_level + 1);
+    if (0 != strcmp(db, subj.db))
+      return false;
+    return (0 == strcmp(table_name, subj.table_name));
+  }
+  bool operator!= (TABLE_LIST &subj) const
+  {
+    return !(*this == subj);
   }
-  bool check();
 };
 
 #endif /* MYSQL_CLIENT */