ALTER DATABASE DEFAULT CHARACTER SET latin1;

sql/mysql_priv.h

@@ -289,7 +289,8 @@ inline THD *_current_thd(void)
 
 #define prepare_execute(A) ((A)->command == COM_EXECUTE)
 
-int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent);
+int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create, bool silent);
+int mysql_alter_db(THD *thd, char *db, HA_CREATE_INFO *create, bool silent);
 int mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent);
 void mysql_binlog_send(THD* thd, char* log_ident, ulong pos, ushort flags);
 int mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists);

sql/sql_db.cc

@@ -31,6 +31,96 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp,
 				 const char *db, const char *path,
 				 uint level);
 
+/* 
+    Create database options file:
+    Currently databse default charset is only stored there.
+*/
+
+static int write_db_opt(THD *thd, char *db, HA_CREATE_INFO *create, char *fn)
+{
+  register File file;
+    char buf[256]; // Should be enough
+  int error=0;
+
+  if ((file=my_create(fn,CREATE_MODE,O_RDWR | O_TRUNC,MYF(MY_WME))) >= 0)
+  {
+    sprintf(buf,"default-character-set=%s\n",
+		 (create && create->table_charset) ? 
+		 create->table_charset->name : "DEFAULT");
+    
+    if (my_write(file,(byte*)buf,strlen(buf),MYF(MY_NABP+MY_WME)))
+    {
+      // QQ : should we send more suitable error message?
+      my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
+      error = -1;
+      goto exit;
+    }
+    my_close(file,MYF(0));
+  }
+  else
+  {
+    // QQ : should we send more suitable error message?
+    my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
+    error = -1;
+    goto exit;
+  }
+exit:
+  return error;
+}
+
+
+  /* 
+    Load database options file:
+  */
+static int load_db_opt(THD *thd,char *fn)
+{
+  register File file;
+  char buf[256]="";
+
+  if ((file=my_open(fn,O_RDWR|O_BINARY,MYF(MY_WME))) >= 0)
+  {
+    int nbytes=my_read(file,(byte*)buf,sizeof(buf)-1,MYF(0));
+    if ( nbytes >= 0 )
+    {
+      char *ln=buf;
+      char *pe=buf+nbytes;
+
+      buf[nbytes]='\0';
+
+      for ( ln=buf; ln<pe; )
+      {
+	char *le,*val;
+	for ( le=ln, val=0 ; le<pe ; le++ )
+	{
+	  switch(le[0])
+	  {
+	    case '=':
+	      le[0]='\0';
+	      val=le+1;
+	      le++;
+	      break;
+	    case '\r':
+	    case '\n':
+	      le[0]='\0';
+	      le++;
+	      for( ; (le[0]=='\r' || le[0]=='\n') ; le++);
+	      if (!strcmp(ln,"default-character-set") && val && val[0])
+	      {
+		thd->db_charset=get_charset_by_name(val, MYF(0));
+	      }
+	      goto cnt;
+	      break;
+	  }
+	}
+cnt:
+	ln=le;
+      }
+    }
+    my_close(file,MYF(0));
+  }
+  return 0;
+}
+
 /* db-name is already validated when we come here */
 
 int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent)
@@ -39,10 +129,10 @@ int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent
   MY_DIR *dirp;
   long result=1;
   int error = 0;
-  DBUG_ENTER("mysql_create_db");
-  register File file;
   uint create_options = create_info ? create_info->options : 0;
   
+  DBUG_ENTER("mysql_create_db");
+  
   VOID(pthread_mutex_lock(&LOCK_mysql_create_db));
 
   // do not create database if another thread is holding read lock
@@ -77,43 +167,81 @@ int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent
     }
   }
 
-  /* 
-    Create database options file:
-    Currently databse default charset is only stored there.
-  */
-
   strcat(path,"/");
   unpack_dirname(path,path);
   strcat(path,MY_DB_OPT_FILE);
-  if ((file=my_create(path,CREATE_MODE,O_RDWR | O_TRUNC,MYF(MY_WME))) >= 0)
-  {
-    sprintf(path,"default-character-set=%s\n",
-		 (create_info && create_info->table_charset) ? 
-		 create_info->table_charset->name : "DEFAULT");
+  if ((error=write_db_opt(thd,db,create_info,path)))
+    goto exit;
   
-    if (my_write(file,(byte*) path,strlen(path),MYF(MY_NABP+MY_WME)))
+  if (!silent)
   {
-      // QQ : should we send more suitable error message?
-      my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
-      error = -1;
-      goto exit;
+    if (!thd->query)
+    {
+      thd->query = path;
+      thd->query_length = (uint) (strxmov(path,"create database ", db, NullS)-
+				  path);
     }
-    my_close(file,MYF(0));
+    {
+      mysql_update_log.write(thd,thd->query, thd->query_length);
+      if (mysql_bin_log.is_open())
+      {
+	Query_log_event qinfo(thd, thd->query);
+	mysql_bin_log.write(&qinfo);
       }
-  else
+    }
+    if (thd->query == path)
     {
-    // QQ : should we send more suitable error message?
-    my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
-    error = -1;
-    goto exit;
+      thd->query = 0; // just in case
+      thd->query_length = 0;
+    }
+    send_ok(&thd->net, result);
   }
 
+exit:
+  start_waiting_global_read_lock(thd);
+exit2:
+  VOID(pthread_mutex_unlock(&LOCK_mysql_create_db));
+  DBUG_RETURN(error);
+}
+
+
+/* db-name is already validated when we come here */
+
+int mysql_alter_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent)
+{
+  char	 path[FN_REFLEN+16];
+  MY_DIR *dirp;
+  long result=1;
+  int error = 0;
+  DBUG_ENTER("mysql_create_db");
+  register File file;
+  uint create_options = create_info ? create_info->options : 0;
+
+  printf("alter database\n");
+
+  VOID(pthread_mutex_lock(&LOCK_mysql_create_db));
+
+  // do not alter database if another thread is holding read lock
+  if (wait_if_global_read_lock(thd,0))
+  {
+    error= -1;
+    goto exit2;
+  }
+
+  /* Check directory */
+  (void)sprintf(path,"%s/%s", mysql_data_home, db);
+  strcat(path,"/");
+  unpack_dirname(path,path);			// Convert if not unix
+  strcat(path,MY_DB_OPT_FILE);
+  if ((error=write_db_opt(thd,db,create_info,path)))
+    goto exit;
+
   if (!silent)
   {
     if (!thd->query)
     {
       thd->query = path;
-      thd->query_length = (uint) (strxmov(path,"create database ", db, NullS)-
+      thd->query_length = (uint) (strxmov(path,"alter database ", db, NullS)-
 				  path);
     }
     {
@@ -139,6 +267,10 @@ exit2:
   DBUG_RETURN(error);
 }
 
+
+
+
+
 const char *del_exts[]= {".frm", ".BAK", ".TMD",".opt", NullS};
 static TYPELIB deletable_extentions=
 {array_elements(del_exts)-1,"del_exts", del_exts};
@@ -368,7 +500,6 @@ bool mysql_change_db(THD *thd,const char *name)
   char	path[FN_REFLEN];
   uint db_access;
   DBUG_ENTER("mysql_change_db");
-  register File file;
 
   if (!dbname || !(db_length=strip_sp(dbname)))
   {
@@ -419,53 +550,11 @@ bool mysql_change_db(THD *thd,const char *name)
   thd->db_length=db_length;
   thd->db_access=db_access;
 
-  /* 
-    Load database options file:
-  */
-
   strcat(path,"/");
   unpack_dirname(path,path);
   strcat(path,MY_DB_OPT_FILE);
-  if ((file=my_open(path,O_RDWR|O_BINARY,MYF(MY_WME))) >= 0)
-  {
-    int nbytes=my_read(file,(byte*) path,sizeof(path),MYF(0));
-    if ( nbytes >= 0 )
-    {
-      char *ln=path;
-      char *pe=path+nbytes;
+  load_db_opt(thd,path);
 
-      path[nbytes]='\0';
-      for ( ln=path; ln<pe; )
-      {
-	char *le,*val;
-	for ( le=ln, val=0 ; le<pe ; le++ )
-	{
-	  switch(le[0])
-	  {
-	    case '=':
-	      le[0]='\0';
-	      val=le+1;
-	      le++;
-	      break;
-	    case '\r':
-	    case '\n':
-	      le[0]='\0';
-	      le++;
-	      for( ; (le[0]=='\r' || le[0]=='\n') ; le++);
-	      if (!strcmp(ln,"default-character-set") && val && val[0])
-	      {
-		thd->db_charset=get_charset_by_name(val, MYF(0));
-	      }
-	      goto cnt;
-	      break;
-	  }
-	}
-cnt:
-	ln=le;
-      }
-    }
-    my_close(file,MYF(0));
-  }
 
   DBUG_RETURN(0);
 }

sql/sql_lex.h

@@ -44,7 +44,8 @@ enum enum_sql_command {
   SQLCOM_SHOW_GRANTS, SQLCOM_SHOW_CREATE, SQLCOM_SHOW_CHARSETS,
 
   SQLCOM_LOAD,SQLCOM_SET_OPTION,SQLCOM_LOCK_TABLES,SQLCOM_UNLOCK_TABLES,
-  SQLCOM_GRANT, SQLCOM_CHANGE_DB, SQLCOM_CREATE_DB, SQLCOM_DROP_DB,
+  SQLCOM_GRANT, 
+  SQLCOM_CHANGE_DB, SQLCOM_CREATE_DB, SQLCOM_DROP_DB, SQLCOM_ALTER_DB,
   SQLCOM_REPAIR, SQLCOM_REPLACE, SQLCOM_REPLACE_SELECT, 
   SQLCOM_CREATE_FUNCTION, SQLCOM_DROP_FUNCTION,
   SQLCOM_REVOKE,SQLCOM_OPTIMIZE, SQLCOM_CHECK,

sql/sql_parse.cc

@@ -2328,6 +2328,23 @@ mysql_execute_command(void)
     res=mysql_rm_db(thd,lex->name,lex->drop_if_exists,0);
     break;
   }
+  case SQLCOM_ALTER_DB:
+  {
+    if (!strip_sp(lex->name) || check_db_name(lex->name))
+    {
+      net_printf(&thd->net,ER_WRONG_DB_NAME, lex->name);
+      break;
+    }
+    if (check_access(thd,DROP_ACL,lex->name,0,1))
+      break;
+    if (thd->locked_tables || thd->active_transaction())
+    {
+      send_error(&thd->net,ER_LOCK_OR_ACTIVE_TRANSACTION);
+      goto error;
+    }
+    res=mysql_alter_db(thd,lex->name,&lex->create_info,0);
+    break;
+  }
   case SQLCOM_CREATE_FUNCTION:
     if (check_access(thd,INSERT_ACL,"mysql",0,1))
       break;

sql/sql_yacc.yy

@@ -885,12 +885,7 @@ create_table_option:
 	    table_list->next=0;
 	    lex->create_info.used_fields|= HA_CREATE_USED_UNION;
 	  }
-	| CHARSET EQ DEFAULT
-	  {
-	    Lex->create_info.table_charset=NULL;
-	    Lex->create_info.used_fields|= HA_CREATE_USED_CHARSET;
-	  }
-	| CHARSET EQ charset
+	| CHARSET EQ charset_or_nocharset
 	  { 
 	    Lex->create_info.table_charset=Lex->charset;
 	    Lex->create_info.used_fields|= HA_CREATE_USED_CHARSET;
@@ -1139,6 +1134,10 @@ charset:
 	  }
 	};
 
+charset_or_nocharset:
+	charset
+	| DEFAULT {Lex->charset=NULL; }
+
 opt_binary:
 	/* empty */		{ Lex->charset=NULL; }
 	| BINARY		{ Lex->type|=BINARY_FLAG; Lex->charset=NULL; }
@@ -1146,7 +1145,7 @@ opt_binary:
 
 default_charset:
 	/* empty */			{ Lex->charset=NULL; }
-	| DEFAULT CHAR_SYM SET charset ;
+	| DEFAULT CHAR_SYM SET charset_or_nocharset ;
 
 references:
 	REFERENCES table_ident
@@ -1271,6 +1270,15 @@ alter:
 	}
 	alter_list;
 
+	| ALTER DATABASE ident default_charset
+	  {
+	    LEX *lex=Lex;
+	    lex->sql_command=SQLCOM_ALTER_DB;
+	    lex->name=$3.str;
+	    lex->create_info.table_charset=lex->charset;
+	  }
+
+
 alter_list:
         | alter_list_item
 	| alter_list ',' alter_list_item;