Commit bc5dc9e0 authored by unknown's avatar unknown
Browse files

renamedb.test, renamedb.result: 

  new file
Many files:
  WL#757 RENAME DATABASE


sql/mysql_priv.h:
  WL#757 RENAME DATABASE
sql/mysqld.cc:
  WL#757 RENAME DATABASE
sql/sql_db.cc:
  WL#757 RENAME DATABASE
sql/sql_lex.h:
  WL#757 RENAME DATABASE
sql/sql_parse.cc:
  WL#757 RENAME DATABASE
sql/sql_rename.cc:
  WL#757 RENAME DATABASE
sql/sql_table.cc:
  WL#757 RENAME DATABASE
sql/sql_yacc.yy:
  WL#757 RENAME DATABASE
parent 3a2b70f8

mysql-test/r/renamedb.result

0 → 100644
+29 −0
Original line number Diff line number Diff line 
drop database if exists testdb1;

create database testdb1 default character set latin2;

use testdb1;

create table t1 (a int);

insert into t1 values (1),(2),(3);

show create database testdb1;

Database	Create Database

testdb1	CREATE DATABASE `testdb1` /*!40100 DEFAULT CHARACTER SET latin2 */

show tables;

Tables_in_testdb1

t1

rename database testdb1 to testdb2;

show create database testdb1;

ERROR 42000: Unknown database 'testdb1'

show create database testdb2;

Database	Create Database

testdb2	CREATE DATABASE `testdb2` /*!40100 DEFAULT CHARACTER SET latin2 */

select database();

database()

testdb2

show tables;

Tables_in_testdb2

t1

select a from t1 order by a;

a

1

2

3

drop database testdb2;

mysql-test/t/renamedb.test

0 → 100644
+18 −0
Original line number Diff line number Diff line 
--disable_warnings

drop database if exists testdb1;

--enable_warnings



create database testdb1 default character set latin2;

use testdb1;

create table t1 (a int);

insert into t1 values (1),(2),(3);

show create database testdb1;

show tables;

rename database testdb1 to testdb2;

--error 1049

show create database testdb1;

show create database testdb2;

select database();

show tables;

select a from t1 order by a;

drop database testdb2;

sql/mysql_priv.h

+8 −5
Original line number Diff line number Diff line
@@ -611,6 +611,7 @@ void write_bin_log(THD *thd, bool clear_error, 
bool mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create, bool silent);

bool mysql_alter_db(THD *thd, const char *db, HA_CREATE_INFO *create);

bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent);

bool mysql_rename_db(THD *thd, LEX_STRING *old_db, LEX_STRING *new_db);

void mysql_binlog_send(THD* thd, char* log_ident, my_off_t pos, ushort flags);

void mysql_client_binlog_statement(THD *thd);

bool mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists,
@@ -623,7 +624,7 @@ int mysql_rm_table_part2_with_lock(THD *thd, TABLE_LIST *tables, 
bool quick_rm_table(handlerton *base,const char *db,

                    const char *table_name);

void close_cached_table(THD *thd, TABLE *table);

bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list);

bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent);

bool mysql_change_db(THD *thd,const char *name,bool no_access_check);

void mysql_parse(THD *thd,char *inBuf,uint length);

bool mysql_test_parse_for_slave(THD *thd,char *inBuf,uint length);
@@ -1228,10 +1229,12 @@ uint check_word(TYPELIB *lib, const char *val, const char *end, 
bool is_keyword(const char *name, uint len);



#define MY_DB_OPT_FILE "db.opt"

bool my_database_names_init(void);

void my_database_names_free(void);

bool load_db_opt(THD *thd, const char *path, HA_CREATE_INFO *create);

bool my_dbopt_init(void);

void my_dbopt_cleanup(void);

void my_dbopt_free(void);

extern int creating_database; // How many database locks are made

extern int creating_table;    // How many mysql_create_table() are running



/*

  External variables
@@ -1334,7 +1337,7 @@ extern FILE *bootstrap_file; 
extern int bootstrap_error;

extern FILE *stderror_file;

extern pthread_key(MEM_ROOT**,THR_MALLOC);

extern pthread_mutex_t LOCK_mysql_create_db,LOCK_Acl,LOCK_open,

extern pthread_mutex_t LOCK_mysql_create_db,LOCK_Acl,LOCK_open, LOCK_lock_db,

       LOCK_thread_count,LOCK_mapped_file,LOCK_user_locks, LOCK_status,

       LOCK_error_log, LOCK_delayed_insert, LOCK_uuid_generator,

       LOCK_delayed_status, LOCK_delayed_create, LOCK_crypt, LOCK_timezone,
@@ -1365,7 +1368,7 @@ extern const char *opt_date_time_formats[]; 
extern KNOWN_DATE_TIME_FORMAT known_date_time_formats[];



extern String null_string;

extern HASH open_cache;

extern HASH open_cache, lock_db_cache;

extern TABLE *unused_tables;

extern const char* any_db;

extern struct my_option my_long_options[];

sql/mysqld.cc

+4 −2
Original line number Diff line number Diff line
@@ -1158,7 +1158,7 @@ void clean_up(bool print_message) 
    bitmap_free(&slave_error_mask);

#endif

  my_tz_free();

  my_dbopt_free();

  my_database_names_free();

#ifndef NO_EMBEDDED_ACCESS_CHECKS

  acl_free(1);

  grant_free();
@@ -1274,6 +1274,7 @@ static void wait_for_signal_thread_to_end() 
static void clean_up_mutexes()

{

  (void) pthread_mutex_destroy(&LOCK_mysql_create_db);

  (void) pthread_mutex_destroy(&LOCK_lock_db);

  (void) pthread_mutex_destroy(&LOCK_Acl);

  (void) rwlock_destroy(&LOCK_grant);

  (void) pthread_mutex_destroy(&LOCK_open);
@@ -2829,7 +2830,7 @@ static int init_common_variables(const char *conf_file_name, int argc, 


  if (use_temp_pool && bitmap_init(&temp_pool,0,1024,1))

    return 1;

  if (my_dbopt_init())

  if (my_database_names_init())

    return 1;



  /*
@@ -2883,6 +2884,7 @@ You should consider changing lower_case_table_names to 1 or 2", 
static int init_thread_environment()

{

  (void) pthread_mutex_init(&LOCK_mysql_create_db,MY_MUTEX_INIT_SLOW);

  (void) pthread_mutex_init(&LOCK_lock_db,MY_MUTEX_INIT_SLOW);

  (void) pthread_mutex_init(&LOCK_Acl,MY_MUTEX_INIT_SLOW);

  (void) pthread_mutex_init(&LOCK_open, NULL);

  (void) pthread_mutex_init(&LOCK_thread_count,MY_MUTEX_INIT_FAST);

sql/sql_db.cc

+427 −6
Original line number Diff line number Diff line
@@ -38,6 +38,107 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, 
         

static long mysql_rm_arc_files(THD *thd, MY_DIR *dirp, const char *org_path);

static my_bool rm_dir_w_symlink(const char *org_path, my_bool send_error);





/* Database lock hash */

HASH lock_db_cache;

pthread_mutex_t LOCK_lock_db;

int creating_database= 0;  // how many database locks are made





/* Structure for database lock */

typedef struct my_dblock_st

{

  char *name;        /* Database name        */

  uint name_length;  /* Database length name */

} my_dblock_t;





/*

  lock_db key.

*/



static byte* lock_db_get_key(my_dblock_t *ptr, uint *length,

                             my_bool not_used __attribute__((unused)))

{

  *length= ptr->name_length;

  return (byte*) ptr->name;

}





/*

  Free lock_db hash element.

*/



static void lock_db_free_element(void *ptr)

{

  my_free((gptr) ptr, MYF(0));

}





/*

  Put a database lock entry into the hash.

  

  DESCRIPTION

    Insert a database lock entry into hash.

    LOCK_db_lock must be previously locked.

  

  RETURN VALUES

    0 on success.

    1 on error.

*/



static my_bool lock_db_insert(const char *dbname, uint length)

{

  my_dblock_t *opt;

  my_bool error= 0;

  DBUG_ENTER("lock_db_insert");

  

  safe_mutex_assert_owner(&LOCK_lock_db);



  if (!(opt= (my_dblock_t*) hash_search(&lock_db_cache,

                                        (byte*) dbname, length)))

  { 

    /* Db is not in the hash, insert it */

    char *tmp_name;

    if (!my_multi_malloc(MYF(MY_WME | MY_ZEROFILL),

                         &opt, (uint) sizeof(*opt), &tmp_name, length+1,

                         NullS))

    {

      error= 1;

      goto end;

    }

    

    opt->name= tmp_name;

    strmov(opt->name, dbname);

    opt->name_length= length;

    

    if ((error= my_hash_insert(&lock_db_cache, (byte*) opt)))

    {

      my_free((gptr) opt, MYF(0));

      goto end;

    }

  }



end:

  DBUG_RETURN(error);

}





/*

  Delete a database lock entry from hash.

*/



void lock_db_delete(const char *name, uint length)

{

  my_dblock_t *opt;

  safe_mutex_assert_owner(&LOCK_lock_db);

  opt= (my_dblock_t *)hash_search(&lock_db_cache, (const byte*) name, length);

  DBUG_ASSERT(opt != NULL);

  hash_delete(&lock_db_cache, (byte*) opt);

}





/* Database options hash */

static HASH dboptions;

static my_bool dboptions_init= 0;
@@ -90,10 +191,10 @@ static void free_dbopt(void *dbopt) 




/* 

  Initialize database option hash

  Initialize database option hash and locked database hash.



  SYNOPSIS

    my_dbopt_init()

    my_database_names()



  NOTES

    Must be called before any other database function is called.
@@ -103,7 +204,7 @@ static void free_dbopt(void *dbopt) 
    1	Fatal error

*/



bool my_dbopt_init(void)

bool my_database_names_init(void)

{

  bool error= 0;

  (void) my_rwlock_init(&LOCK_dboptions, NULL);
@@ -113,27 +214,38 @@ bool my_dbopt_init(void) 
    error= hash_init(&dboptions, lower_case_table_names ? 

                     &my_charset_bin : system_charset_info,

                     32, 0, 0, (hash_get_key) dboptions_get_key,

                     free_dbopt,0);

                     free_dbopt,0) ||

           hash_init(&lock_db_cache, lower_case_table_names ? 

                     &my_charset_bin : system_charset_info,

                     32, 0, 0, (hash_get_key) lock_db_get_key,

                     lock_db_free_element,0);



  }

  return error;

}







/* 

  Free database option hash.

  Free database option hash and locked databases hash.

*/



void my_dbopt_free(void)

void my_database_names_free(void)

{

  if (dboptions_init)

  {

    dboptions_init= 0;

    hash_free(&dboptions);

    (void) rwlock_destroy(&LOCK_dboptions);

    hash_free(&lock_db_cache);

  }

}





/*

  Cleanup cached options

*/



void my_dbopt_cleanup(void)

{

  rw_wrlock(&LOCK_dboptions);
@@ -1209,3 +1321,312 @@ bool mysql_change_db(THD *thd, const char *name, bool no_access_check) 
  }

  DBUG_RETURN(0);

}





static int

lock_databases(THD *thd, const char *db1, uint length1,

                         const char *db2, uint length2)

{

  pthread_mutex_lock(&LOCK_lock_db);

  while (!thd->killed &&

         (hash_search(&lock_db_cache,(byte*) db1, length1) ||

          hash_search(&lock_db_cache,(byte*) db2, length2)))

  {

    wait_for_condition(thd, &LOCK_lock_db, &COND_refresh);

    pthread_mutex_lock(&LOCK_lock_db);

  }



  if (thd->killed)

  {

    pthread_mutex_unlock(&LOCK_lock_db);

    return 1;

  }



  lock_db_insert(db1, length1);

  lock_db_insert(db2, length2);

  creating_database++;



  /*

    Wait if a concurent thread is creating a table at the same time.

    The assumption here is that it will not take too long until

    there is a point in time when a table is not created.

  */



  while (!thd->killed && creating_table)

  {

    wait_for_condition(thd, &LOCK_lock_db, &COND_refresh);

    pthread_mutex_lock(&LOCK_lock_db);

  }



  if (thd->killed)

  {

    lock_db_delete(db1, length1);

    lock_db_delete(db2, length2);

    creating_database--;

    pthread_mutex_unlock(&LOCK_lock_db);

    pthread_cond_signal(&COND_refresh);

    return(1);

  }



  /*

    We can unlock now as the hash will protect against anyone creating a table

    in the databases we are using

  */

  pthread_mutex_unlock(&LOCK_lock_db);

  return 0;

}





/*

  Rename database.



  SYNOPSIS

    mysql_rename_db()

    thd                 Thread handler

    olddb               Old database name

    newdb               New database name



  DESCRIPTION

   This function is invoked whenever a RENAME DATABASE query is executed:



     RENAME DATABASE 'olddb' TO 'newdb'.



  NOTES



    If we have managed to rename (move) tables to the new database

    but something failed on a later step, then we store the

    RENAME DATABASE event in the log. mysql_rename_db() is atomic in

    the sense that it will rename all or none of the tables.



  TODO:

    - Better trigger, stored procedure, event, grant handling,

      see the comments below.

      NOTE: It's probably a good idea to call wait_if_global_read_lock()

      once in mysql_rename_db(), instead of locking inside all

      the required functions for renaming triggerts, SP, events, grants, etc.



  RETURN VALUES

    0	ok

    1	error

*/





bool mysql_rename_db(THD *thd, LEX_STRING *old_db, LEX_STRING *new_db)

{

  int error= 0, change_to_newdb= 0;

  char path[FN_REFLEN+16];

  uint length;

  HA_CREATE_INFO create_info;

  MY_DIR *dirp;

  TABLE_LIST *table_list;

  SELECT_LEX *sl= thd->lex->current_select;

  DBUG_ENTER("mysql_rename_db");



  if (lock_databases(thd, old_db->str, old_db->length,

                          new_db->str, new_db->length))

    return 1;



  /*

    Let's remember if we should do "USE newdb" afterwards.

    thd->db will be cleared in mysql_rename_db()

  */

  if (thd->db && !strcmp(thd->db, old_db->str))

    change_to_newdb= 1;



  build_table_filename(path, sizeof(path)-1, old_db->str, "", MY_DB_OPT_FILE);

  if ((load_db_opt(thd, path, &create_info)))

    create_info.default_table_charset= thd->variables.collation_server;



  length= build_table_filename(path, sizeof(path)-1, old_db->str, "", "");

  if (length && path[length-1] == FN_LIBCHAR)

    path[length-1]=0;                            // remove ending '\'

  if ((error= my_access(path,F_OK)))

  {

    my_error(ER_BAD_DB_ERROR, MYF(0), old_db->str);

    goto exit;

  }



  /* Step1: Create the new database */

  if ((error= mysql_create_db(thd, new_db->str, &create_info, 1)))

    goto exit;



  /* Step2: Move tables to the new database */

  if ((dirp = my_dir(path,MYF(MY_DONT_SORT))))

  {

    uint nfiles= (uint) dirp->number_off_files;

    for (uint idx=0 ; idx < nfiles && !thd->killed ; idx++)

    {

      FILEINFO *file= dirp->dir_entry + idx;

      char *extension, tname[FN_REFLEN];

      LEX_STRING table_str;

      DBUG_PRINT("info",("Examining: %s", file->name));



      /* skiping non-FRM files */

      if (my_strcasecmp(files_charset_info,

                        (extension= fn_rext(file->name)), reg_ext))

        continue;



      /* A frm file found, add the table info rename list */

      *extension= '\0';

      

      table_str.length= filename_to_tablename(file->name,

                                              tname, sizeof(tname)-1);

      table_str.str= sql_memdup(tname, table_str.length + 1);

      Table_ident *old_ident= new Table_ident(thd, *old_db, table_str, 0);

      Table_ident *new_ident= new Table_ident(thd, *new_db, table_str, 0);

      if (!old_ident || !new_ident ||

          !sl->add_table_to_list(thd, old_ident, NULL,

                                 TL_OPTION_UPDATING, TL_IGNORE) ||

          !sl->add_table_to_list(thd, new_ident, NULL,

                                 TL_OPTION_UPDATING, TL_IGNORE))

      {

        error= 1;

        my_dirend(dirp);

        goto exit;

      }

    }

    my_dirend(dirp);  

  }



  if ((table_list= thd->lex->query_tables) &&

      (error= mysql_rename_tables(thd, table_list, 1)))

  {

    /*

      Failed to move all tables from the old database to the new one.

      In the best case mysql_rename_tables() moved all tables back to the old

      database. In the worst case mysql_rename_tables() moved some tables

      to the new database, then failed, then started to move the tables back,  and

      then failed again. In this situation we have some tables in the

      old database and some tables in the new database.

      Let's delete the option file, and then the new database directory.

      If some tables were left in the new directory, rmdir() will fail.

      It garantees we never loose any tables.

    */

    build_table_filename(path, sizeof(path)-1, new_db->str,"",MY_DB_OPT_FILE);

    my_delete(path, MYF(MY_WME));

    length= build_table_filename(path, sizeof(path)-1, new_db->str, "", "");

    if (length && path[length-1] == FN_LIBCHAR)

      path[length-1]=0;                            // remove ending '\'

    rmdir(path);

    goto exit;

  }





  /*

    Step3: move all remaining files to the new db's directory.

    Skip db opt file: it's been created by mysql_create_db() in

    the new directory, and will be dropped by mysql_rm_db() in the old one.

    Trigger TRN and TRG files are be moved as regular files at the moment,

    without any special treatment.



    Triggers without explicit database qualifiers in table names work fine: 

      use d1;

      create trigger trg1 before insert on t2 for each row set @a:=1

      rename database d1 to d2;



    TODO: Triggers, having the renamed database explicitely written

    in the table qualifiers.

    1. when the same database is renamed:

        create trigger d1.trg1 before insert on d1.t1 for each row set @a:=1;

        rename database d1 to d2;

      Problem: After database renaming, the trigger's body

               still points to the old database d1.

    2. when another database is renamed:

        create trigger d3.trg1 before insert on d3.t1 for each row

          insert into d1.t1 values (...);

        rename database d1 to d2;

      Problem: After renaming d1 to d2, the trigger's body

               in the database d3 still points to database d1.

  */



  if ((dirp = my_dir(path,MYF(MY_DONT_SORT))))

  {

    uint nfiles= (uint) dirp->number_off_files;

    for (uint idx=0 ; idx < nfiles ; idx++)

    {

      FILEINFO *file= dirp->dir_entry + idx;

      char oldname[FN_REFLEN], newname[FN_REFLEN];

      DBUG_PRINT("info",("Examining: %s", file->name));



      /* skiping . and .. and MY_DB_OPT_FILE */

      if ((file->name[0] == '.' &&

           (!file->name[1] || (file->name[1] == '.' && !file->name[2]))) ||

          !my_strcasecmp(files_charset_info, file->name, MY_DB_OPT_FILE))

        continue;



      /* pass empty file name, and file->name as extension to avoid encoding */

      build_table_filename(oldname, sizeof(oldname)-1,

                           old_db->str, "", file->name);

      build_table_filename(newname, sizeof(newname)-1,

                           new_db->str, "", file->name);

      my_rename(oldname, newname, MYF(MY_WME));

    }

    my_dirend(dirp);  

  }



  /*

    Step4: TODO: moving stored procedures in the 'proc' system table

    We need a new function: sp_move_db_routines(thd, olddb, newdb)

    Which will basically have the same effect with:

    UPDATE proc SET db='newdb' WHERE db='olddb'

    Note, for 5.0 to 5.1 upgrade purposes we don't really need it.



    The biggest problem here is that we can't have a lock on LOCK_open() while

    calling open_table() for 'proc'.



    Two solutions:

    - Start by opening the 'event' and 'proc' (and other) tables for write

      even before creating the 'to' database.  (This will have the nice

      effect of blocking another 'rename database' while the lock is active).

    - Use the solution "Disable create of new tables during lock table"



    For an example of how to read through all rows, see:

    sql_help.cc::search_topics()

  */



  /*

    Step5: TODO: moving events in the 'event' system table

    We need a new function evex_move_db_events(thd, olddb, newdb)

    Which will have the same effect with:

    UPDATE event SET db='newdb' WHERE db='olddb'

    Note, for 5.0 to 5.1 upgrade purposes we don't really need it.

  */



  /*

    Step6: TODO: moving grants in the 'db', 'tables_priv', 'columns_priv'.

    Update each grant table, doing the same with:

    UPDATE system_table SET db='newdb' WHERE db='olddb'

  */



  /*

    Step7: drop the old database.

    remove_db_from_cache(olddb) and query_cache_invalidate(olddb)

    are done inside mysql_rm_db(), no needs to execute them again.

    mysql_rm_db() also "unuses" if we drop the current database.

  */

  error= mysql_rm_db(thd, old_db->str, 0, 1);



  /* Step8: logging */

  if (mysql_bin_log.is_open())

  {

    Query_log_event qinfo(thd, thd->query, thd->query_length, 0, TRUE);

    thd->clear_error();

    mysql_bin_log.write(&qinfo);

  }



  /* Step9: Let's do "use newdb" if we renamed the current database */

  if (change_to_newdb)

    error|= mysql_change_db(thd, new_db->str, 0);



exit:

  pthread_mutex_lock(&LOCK_lock_db);

  /* Remove the databases from db lock cache */

  lock_db_delete(old_db->str, old_db->length);

  lock_db_delete(new_db->str, new_db->length);

  creating_database--;

  /* Signal waiting CREATE TABLE's to continue */

  pthread_cond_signal(&COND_refresh);

  pthread_mutex_unlock(&LOCK_lock_db);



  DBUG_RETURN(error);

}