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    Fix for bug#22369: Alter table rename combined · ab31e427
    unknown authored
    with other alterations causes lost tables
    
    Using RENAME clause combined with other clauses of ALTER TABLE led to
    data loss (the data was there but not accessible). This could happen if the
    changes do not change the table much. Adding and droppping of fields and
    indices was safe. Renaming a column with MODIFY or CHANGE was unsafe operation,
    if the actual column didn't change (changing from int to int, which is a noop)
      
    Depending on the storage engine (SE) the behavior is different:
    1)MyISAM/MEMORY - the ALTER TABLE statement completes
      without any error but next SELECT against the new table fails.
    2)InnoDB (and every other transactional table) - The ALTER TABLE statement
      fails. There are the the following files in the db dir -
      `new_table_name.frm` and a temporary table's frm. If the SE is file
      based, then the data and index files will be present but with the old
      names. What happens is that for InnoDB the table is not renamed in the
      internal DDIC.
    
    Fixed by adding additional call to mysql_rename_table() method, which should
    not include FRM file rename, because it has been already done during file
    names juggling.
    
    
    mysql-test/r/alter_table.result:
      update result
    mysql-test/r/grant.result:
      update result
    mysql-test/t/alter_table.test:
      2006/11/29 11:46:23+01:00 andrey@example.com +44 -9
      Error to bug number
          
      Added test case for #22369: Alter table rename combined
      with other alterations causes lost tables
    mysql-test/t/grant.test:
      add test for bug#22369 - alter table was missing check
      for DROP_ACL when ALTER_RENAME clause is specified. Synchronise
      with RENAME TABLE DDL.
    sql/mysql_priv.h:
      Add a new flag for mysql_rename_table()
    sql/sql_parse.cc:
      To be consistent with SQLCOM_RENAME_TABLE, SQLCOM_ALTER_TABLE has
      to check for DROP_ACL if there is ALTER_RENAME flag set.
    sql/sql_table.cc:
      ALTER_RENAME, the data and index files weren't renamed in the engine
      but only the FRM was new, when the tables old and new tables are compatible.
      In the chain of FRM renames we add a call to mysql_rename_table() which should
      instruct the engine to rename the table but not rename the FRM.
      This bug was there only in 5.1 branch. 4.1 and 5.0 always do copy data on RENAME
      if there are more clauses than just rename.
    ab31e427
grant.result 49.6 KB