Changed SQL variable delay_key_write to an enum

able delay_key_write as default (as it was in 4.0.2)

Docs/manual.texi

@@ -14186,7 +14186,10 @@ Set the default character set.  @xref{Character sets}.
 @item --default-table-type=type
 Set the default table type for tables.  @xref{Table types}.
 
-@item --delay-key-write-for-all-tables
+@item --delay-key-write[= OFF | ON | ALL}
+How MyISAM @code{DELAYED KEYS} should be used. @xref{Server parameters}.
+
+@item --delay-key-write-for-all-tables;  In MySQL 4.0.3 you should use --delay-key-write=ALL instead.
 Don't flush key buffers between writes for any @code{MyISAM} table.
 @xref{Server parameters}.
 
@@ -14321,7 +14324,7 @@ correct it to stay within a given range and also adjusts the value a
 little to fix for the used algorithm.
 
 @item --safe-mode
-Skip some optimise stages.  Implies @code{--skip-delay-key-write}.
+Skip some optimise stages.
 
 @item --safe-show-database
 With this option, the @code{SHOW DATABASES} command returns only those
@@ -14340,8 +14343,8 @@ Turn off the ability to select and insert at the same time on @code{MyISAM}
 tables. (This is only to be used if you think you have found a bug in this
 feature.)
 
-@item --skip-delay-key-write
-Ignore the @code{delay_key_write} option for all tables.
+@item --skip-delay-key-write; In MySQL 4.0.3 you should use --delay-key-write=OFF instead.
+Ignore the @code{DELAY_KEY_WRITE} option for all tables.
 @xref{Server parameters}.
 
 @item --skip-grant-tables
@@ -14370,8 +14373,7 @@ Don't listen for TCP/IP connections at all.  All interaction with
 recommended for systems where only local requests are allowed.  @xref{DNS}.
 
 @item --skip-new
-Don't use new, possible wrong routines.  Implies @code{--skip-delay-key-write}.
-This will also set default table type to @code{ISAM}.  @xref{ISAM}.
+Don't use new, possible wrong routines.
 
 @item --skip-symlink
 Don't delete or rename files that a symlinked file in the data directory
@@ -19848,16 +19850,20 @@ packet before responding with @code{Bad handshake}.
 The value of the @code{--datadir} option.
 
 @item @code{delay_key_write}
-If enabled (is on by default), MySQL will honor the
-@code{DELAY_KEY_WRITE} option for @code{CREATE TABLE}.  This means that the
-key buffer for tables with this option will not get flushed on every
-index update, but only when a table is closed.  This will speed up
-writes on keys a lot, but you should add automatic checking of all tables
-with @code{myisamchk --fast --force} if you use this.  Note that if you
-start @code{mysqld} with the @code{--delay-key-write-for-all-tables}
-option this means that all tables will be treated as if they were
-created with the @code{delay_key_write} option.  You can clear this flag
-by starting @code{mysqld} with @code{--skip-new} or @code{--safe-mode}.
+Option for MyISAM tables. Can have one of the following values:
+
+@multitable @columnfractions .30 .70
+@item OFF @tab All CREATE TABLE ... DELAYED_KEY_WRITES are ignored.
+@item ON  @tab (default)  MySQL will honor the @code{DELAY_KEY_WRITE} option
+for @code{CREATE TABLE}.
+@item ALL @tab All new opened tables are treated as if they were created with the @code{DELAY_KEY_WRITE} option.
+@end itemize
+
+If @code{DELAY_KEY_WRITE} is enabled this means that the key buffer for
+tables with this option will not get flushed on every index update, but
+only when a table is closed.  This will speed up writes on keys a lot,
+but you should add automatic checking of all tables with @code{myisamchk
+--fast --force} if you use this.
 
 @item @code{delayed_insert_limit}
 After inserting @code{delayed_insert_limit} rows, the @code{INSERT
@@ -19961,7 +19967,7 @@ status} and examine the variables @code{Key_read_requests},
 The @code{Key_write/Key_write_requests} is usually near 1 if you are
 using mostly updates/deletes but may be much smaller if you tend to
 do updates that affect many at the same time or if you are
-using @code{delay_key_write}. @xref{SHOW, , @code{SHOW}}.
+using @code{DELAY_KEY_WRITE}. @xref{SHOW, , @code{SHOW}}.
 
 To get even more speed when writing many rows at the same time, use
 @code{LOCK TABLES}.  @xref{LOCK TABLES, , @code{LOCK TABLES}}.
@@ -24477,7 +24483,7 @@ offset by network delays.
 writes to it, and configure as many slaves as you have the money and
 rackspace for, distributing the reads among the master and the slaves.
 You can also start the slaves with @code{--skip-bdb},
-@code{--low-priority-updates} and @code{--delay-key-write-for-all-tables}
+@code{--low-priority-updates} and @code{--delay-key-write=ALL}
 to get speed improvements for the slave.  In this case the slave will
 use non-transactional @code{MyISAM} tables instead of @code{BDB} tables
 to get more speed.
@@ -28630,7 +28636,7 @@ and if you can use @code{GLOBAL} or @code{SESSION} with them.
 @item concurrent_insert @tab bool @tab GLOBAL
 @item connect_timeout @tab num @tab GLOBAL
 @item convert_character_set @tab string @tab SESSION
-@item delay_key_write @tab bool @tab GLOBAL
+@item delay_key_write @tab OFF | ON | ALL @tab GLOBAL
 @item delayed_insert_limit @tab num @tab GLOBAL
 @item delayed_insert_timeout @tab num @tab GLOBAL
 @item delayed_queue_size @tab num @tab GLOBAL
@@ -28717,6 +28723,7 @@ Here is a description of some of the variables:
 @item identity @tab Alias for last_insert_id (Sybase compatiblity)
 @item sql_low_priority_updates @tab Alias for low_priority_updates
 @item sql_max_join_size @tab Alias for max_join_size
+@item delay_key_write_for_all_tables @tab If this and delay_key_write is set then all new MyISAM tables that are opened will use delayed key writes.
 @item version @tab Alias for VERSION() (Sybase (?) compatability)
 @end multitable
 
@@ -37687,7 +37694,7 @@ The following options to @code{mysqld} can be used to change the behaviour of
 @item @strong{Option} @tab @strong{Description}
 @item @code{--myisam-recover=#} @tab Automatic recovery of crashed tables.
 @item @code{-O myisam_sort_buffer_size=#} @tab Buffer used when recovering tables.
-@item @code{--delay-key-write-for-all-tables} @tab Don't flush key buffers between writes for any MyISAM table
+@item @code{--delay-key-write=ALL} @tab Don't flush key buffers between writes for any MyISAM table
 @item @code{-O myisam_max_extra_sort_file_size=#} @tab Used to help MySQL to decide when to use the slow but safe key cache index create method. @strong{Note} that this parameter is given in megabytes before 4.0.3 and in bytes starting from this version.
 @item @code{-O myisam_max_sort_file_size=#} @tab Don't use the fast sort index method to created index if the temporary file would get bigger than this.  @strong{Note} that this parameter is given in megabytes before 4.0.3 and in bytes starting from this version.
 @item @code{-O bulk_insert_buffer_size=#} @tab Size of tree cache used in bulk insert optimisation. @strong{Note} that this is a limit @strong{per thread}!
@@ -50230,6 +50237,9 @@ each individual 4.0.x release.
 
 @itemize @bullet
 @item
+Changed variable @code{DELAY_KEY_WRITE} to an enum to allow one set
+@code{DELAY_KEY_WRITE} for all tables without taking down the server.
+@item
 Changed behavior of @code{IF(condition,column,NULL)} so that it returns
 the value of the column type.
 @item

mysql-test/r/type_decimal.result

@@ -267,7 +267,7 @@ insert into t1 values (-.1),(+.1),(.1);
 insert into t1 values (00000000000001),(+0000000000001),(-0000000000001);
 insert into t1 values (+111111111.11),(111111111.11),(-11111111.11);
 insert into t1 values (-111111111.11),(+1111111111.11),(1111111111.11);
-insert into t1 values (1e+1000),(1e-1000),(-1e+1000);
+insert into t1 values (1e+100),(1e-100),(-1e+100);
 insert into t1 values (123.4e0),(123.4e+2),(123.4e-2),(123e1),(123e+0);
 select * from t1;
 a

mysql-test/r/variables.result

@@ -219,7 +219,21 @@ set convert_character_set=cp1251_koi8;
 set convert_character_set=default;
 set @@global.concurrent_insert=1;
 set global connect_timeout=100;
+select @@delay_key_write;
+@@delay_key_write
+ON
+set global delay_key_write="OFF";
+select @@delay_key_write;
+@@delay_key_write
+OFF
+set global delay_key_write=ALL;
+select @@delay_key_write;
+@@delay_key_write
+ALL
 set global delay_key_write=1;
+select @@delay_key_write;
+@@delay_key_write
+ON
 set global delayed_insert_limit=100;
 set global delayed_insert_timeout=100;
 set global delayed_queue_size=100;

mysql-test/t/type_decimal.test

@@ -195,7 +195,7 @@ insert into t1 values (-.1),(+.1),(.1);
 insert into t1 values (00000000000001),(+0000000000001),(-0000000000001);
 insert into t1 values (+111111111.11),(111111111.11),(-11111111.11);
 insert into t1 values (-111111111.11),(+1111111111.11),(1111111111.11);
-insert into t1 values (1e+1000),(1e-1000),(-1e+1000);
+insert into t1 values (1e+100),(1e-100),(-1e+100);
 insert into t1 values (123.4e0),(123.4e+2),(123.4e-2),(123e1),(123e+0);
 select * from t1;
 drop  table t1;

mysql-test/t/variables.test

@@ -143,7 +143,13 @@ set convert_character_set=cp1251_koi8;
 set convert_character_set=default;
 set @@global.concurrent_insert=1;
 set global connect_timeout=100;
+select @@delay_key_write;
+set global delay_key_write="OFF";
+select @@delay_key_write;
+set global delay_key_write=ALL;
+select @@delay_key_write;
 set global delay_key_write=1;
+select @@delay_key_write;
 set global delayed_insert_limit=100;
 set global delayed_insert_timeout=100;
 set global delayed_queue_size=100;

sql/ha_innodb.cc

@@ -266,50 +266,59 @@ void
 innobase_mysql_print_thd(
 /*=====================*/
 	char*   buf,	/* in/out: buffer where to print, must be at least
-			300 bytes */
+			400 bytes */
         void*   input_thd)/* in: pointer to a MySQL THD object */
 {
   	THD*    thd;
+	char*   old_buf = buf;
 
         thd = (THD*) input_thd;
 
-	/*  We can't use value of sprintf() as this is not portable */
-  	buf+= my_sprintf(buf,
+	/*  We cannot use the return value of normal sprintf() as this is
+	not portable to some old non-Posix Unixes, e.g., some old SCO
+	Unixes */
+
+  	buf += my_sprintf(buf,
 			 (buf, "MySQL thread id %lu, query id %lu",
 			  thd->thread_id, thd->query_id));
-    	if (thd->host)
-	{
-	  *buf++=' ';
-	  buf=strnmov(buf, thd->host, 30);
+    	if (thd->host) {
+	        *buf = ' ';
+		buf++;
+	        buf = strnmov(buf, thd->host, 30);
   	}
 
-  	if (thd->ip)
-	{
-	  *buf++=' ';
+  	if (thd->ip) {
+	        *buf = ' ';
+		buf++;
 	        buf=strnmov(buf, thd->ip, 20);
   	}
 
-  	if (thd->user)
-	{
-	  *buf++=' ';
+  	if (thd->user) {
+	        *buf = ' ';
+		buf++;
 	        buf=strnmov(buf, thd->user, 20);
   	}
 
-  	if (thd->proc_info)
-	{
-	  *buf++=' ';
+  	if (thd->proc_info) {
+	        *buf = ' ';
+		buf++;
 	        buf=strnmov(buf, thd->proc_info, 50);
   	}
 
-  	if (thd->query)
-	{
-	  *buf++=' ';
+  	if (thd->query) {
+	        *buf = '\n';
+		buf++;
 	        buf=strnmov(buf, thd->query, 150);
   	}  
-	buf[0]='\n';
-	buf[1]=0;
 
- 	ut_a(strlen(buf) < 400);
+	buf[0] = '\n';
+	buf[1] = '\0'; /* Note that we must put a null character here to end
+		       the printed string */
+
+	/* We test the printed length did not overrun the buffer length of
+	400 bytes */
+
+ 	ut_a(strlen(old_buf) < 400);
 }
 }
 

sql/mysql_priv.h

@@ -635,6 +635,7 @@ extern ulong specialflag, current_pid;
 
 extern uint test_flags,select_errors,ha_open_options;
 extern uint protocol_version,dropping_tables;
+extern uint delay_key_write_options;
 extern bool opt_endinfo, using_udf_functions, locked_in_memory;
 extern bool opt_using_transactions, use_temp_pool, mysql_embedded;
 extern bool using_update_log, opt_large_files;

sql/mysqld.cc

@@ -47,6 +47,12 @@
 #define SIGNAL_THD
 #endif
 
+#ifdef PURIFY
+#define IF_PURIFY(A,B) (A)
+#else
+#define IF_PURIFY(A,B) (B)
+#endif
+
 /* stack traces are only supported on linux intel */
 #if defined(__linux__)  && defined(__i386__) && defined(USE_PSTACK)
 #define	HAVE_STACK_TRACE_ON_SEGV
@@ -259,6 +265,7 @@ bool opt_log, opt_update_log, opt_bin_log, opt_slow_log;
 bool opt_disable_networking=0, opt_skip_show_db=0;
 bool opt_enable_named_pipe= 0;
 my_bool opt_local_infile, opt_external_locking, opt_slave_compressed_protocol;
+uint delay_key_write_options= (uint) DELAY_KEY_WRITE_ON;
 
 static bool opt_do_pstack = 0;
 static ulong opt_specialflag=SPECIAL_ENGLISH;
@@ -2816,8 +2823,8 @@ enum options {
   OPT_FLUSH,                   OPT_SAFE, 
   OPT_BOOTSTRAP,               OPT_SKIP_SHOW_DB,
   OPT_TABLE_TYPE,              OPT_INIT_FILE,   
-  OPT_DELAY_KEY_WRITE,         OPT_SLOW_QUERY_LOG, 
-  OPT_USE_DELAY_KEY_WRITE,     OPT_CHARSETS_DIR,
+  OPT_DELAY_KEY_WRITE_ALL,     OPT_SLOW_QUERY_LOG, 
+  OPT_DELAY_KEY_WRITE,	       OPT_CHARSETS_DIR,
   OPT_BDB_HOME,                OPT_BDB_LOG,  
   OPT_BDB_TMP,                 OPT_BDB_NOSYNC,
   OPT_BDB_LOCK,                OPT_BDB_SKIP, 
@@ -2994,9 +3001,11 @@ struct my_option my_long_options[] =
   {"default-table-type", OPT_TABLE_TYPE,
    "Set the default table type for tables", 0, 0,
    0, GET_NO_ARG, REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
-  {"delay-key-write-for-all-tables", OPT_DELAY_KEY_WRITE, 
-   "Don't flush key buffers between writes for any MyISAM table", 0, 0, 0,
-   GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0},
+  {"delay-key-write", OPT_DELAY_KEY_WRITE, "Type of DELAY_KEY_WRITE",
+   0,0,0, GET_STR, OPT_ARG, 0, 0, 0, 0, 0, 0},
+  {"delay-key-write-for-all-tables", OPT_DELAY_KEY_WRITE_ALL,
+   "Don't flush key buffers between writes for any MyISAM table (Depricated option, use --delay-key-write=all instead)",
+   0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0},
   {"enable-locking", OPT_ENABLE_LOCK,
    "Depricated option, use --external-locking instead",
    (gptr*) &opt_external_locking, (gptr*) &opt_external_locking,
@@ -3260,10 +3269,6 @@ struct my_option my_long_options[] =
    "Use concurrent insert with MyISAM. Disable with prefix --skip-",
    (gptr*) &myisam_concurrent_insert, (gptr*) &myisam_concurrent_insert,
    0, GET_BOOL, NO_ARG, 1, 0, 0, 0, 0, 0},
-  {"delay-key-write", OPT_USE_DELAY_KEY_WRITE,
-   "Use delay_key_write option for all tables. Disable with prefix --skip-",
-   (gptr*) &myisam_delay_key_write, (gptr*) &myisam_delay_key_write, 0,
-   GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
   {"skip-grant-tables", OPT_SKIP_GRANT,
    "Start without grant tables. This gives all users FULL ACCESS to all tables!",
    (gptr*) &opt_noacl, (gptr*) &opt_noacl, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0,
@@ -3335,8 +3340,8 @@ struct my_option my_long_options[] =
    0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
 #ifdef USE_SYMDIR
   {"use-symbolic-links", 's', "Enable symbolic link support",
-   (gptr*) &my_use_symdir, (gptr*) &my_use_symdir, 0, GET_BOOL, NO_ARG, 0, 0,
-   0, 0, 0, 0},
+   (gptr*) &my_use_symdir, (gptr*) &my_use_symdir, 0, GET_BOOL, NO_ARG,
+   USE_PURIFY(0,1), 0, 0, 0, 0, 0},
 #endif
   {"user", 'u', "Run mysqld daemon as user", (gptr*) &mysqld_user,
    (gptr*) &mysqld_user, 0, GET_STR, REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
@@ -3382,7 +3387,7 @@ struct my_option my_long_options[] =
     (gptr*) &connect_timeout, (gptr*) &connect_timeout,
    0, GET_ULONG, REQUIRED_ARG, CONNECT_TIMEOUT, 2, LONG_TIMEOUT, 0, 1, 0 },
   {"delayed_insert_timeout", OPT_DELAYED_INSERT_TIMEOUT,
-   "How long a INSERT DELAYED thread should wait for INSERT statements before terminating.",
+   "Ho wlong a INSERT DELAYED thread should wait for INSERT statements before terminating.",
    (gptr*) &delayed_insert_timeout, (gptr*) &delayed_insert_timeout, 0,
    GET_ULONG, REQUIRED_ARG, DELAYED_WAIT_TIMEOUT, 1, LONG_TIMEOUT, 0, 1, 0},
   {"delayed_insert_limit", OPT_DELAYED_INSERT_LIMIT,
@@ -4119,22 +4124,22 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
     break;
   case (int) OPT_SKIP_NEW:
     opt_specialflag|= SPECIAL_NO_NEW_FUNC;
-    myisam_delay_key_write=0;
+    delay_key_write_options= (uint) DELAY_KEY_WRITE_NONE;
     myisam_concurrent_insert=0;
     myisam_recover_options= HA_RECOVER_NONE;
     my_disable_symlinks=1;
     my_use_symdir=0;
     have_symlink=SHOW_OPTION_DISABLED;
-    ha_open_options&= ~HA_OPEN_ABORT_IF_CRASHED;
+    ha_open_options&= ~(HA_OPEN_ABORT_IF_CRASHED | HA_OPEN_DELAY_KEY_WRITE);
 #ifdef HAVE_QUERY_CACHE
     query_cache_size=0;
 #endif
     break;
   case (int) OPT_SAFE:
     opt_specialflag|= SPECIAL_SAFE_MODE;
-    myisam_delay_key_write=0;
+    delay_key_write_options= (uint) DELAY_KEY_WRITE_NONE;
     myisam_recover_options= HA_RECOVER_NONE;	// To be changed
-    ha_open_options&= ~HA_OPEN_ABORT_IF_CRASHED;
+    ha_open_options&= ~(HA_OPEN_ABORT_IF_CRASHED | HA_OPEN_DELAY_KEY_WRITE);
     break;
   case (int) OPT_SKIP_PRIOR:
     opt_specialflag|= SPECIAL_NO_PRIOR;
@@ -4239,9 +4244,25 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
   case OPT_SERVER_ID:
     server_id_supplied = 1;
     break;
+  case OPT_DELAY_KEY_WRITE_ALL:
+    if (argument != disabled_my_option)
+      argument= (char*) "ALL";
+    /* Fall through */
   case OPT_DELAY_KEY_WRITE:
-    ha_open_options|=HA_OPEN_DELAY_KEY_WRITE;
-    myisam_delay_key_write=1;
+    if (argument == disabled_my_option)
+      delay_key_write_options= (uint) DELAY_KEY_WRITE_NONE;
+    else if (! argument)
+      delay_key_write_options= (uint) DELAY_KEY_WRITE_ON;
+    else
+    {
+      int type;
+      if ((type=find_type(argument, &delay_key_write_typelib, 2)) <= 0)
+      {
+	fprintf(stderr,"Unknown delay_key_write type: %s\n",argument);
+	exit(1);
+      }
+      delay_key_write_options= (uint) type-1;
+    }
     break;
   case OPT_CHARSETS_DIR:
     strmake(mysql_charsets_dir, argument, sizeof(mysql_charsets_dir)-1);
@@ -4364,18 +4385,22 @@ static void get_options(int argc,char **argv)
 {
   int ho_error;
 
-  myisam_delay_key_write=1;			// Allow use of this
-#ifndef HAVE_purify
-  my_use_symdir=1;				// Use internal symbolic links
+  if ((ho_error=handle_options(&argc, &argv, my_long_options, get_one_option)))
+    exit(ho_error);
+
+#ifdef HAVE_BROKEN_REALPATH
+  my_use_symdir=0;
+  my_disable_symlinks=1;
+  have_symlink=SHOW_OPTION_NO;
 #else
-  /* Symlinks gives too many warnings with purify */
+  if (!my_use_symdir)
+  {
     my_disable_symlinks=1;
-  my_use_symdir=0;
     have_symlink=SHOW_OPTION_DISABLED;
+  }
 #endif
-
-  if ((ho_error=handle_options(&argc, &argv, my_long_options, get_one_option)))
-    exit(ho_error);
+  /* Set global MyISAM variables from delay_key_write_options */
+  fix_delay_key_write((THD*) 0, OPT_GLOBAL);
 
   if (mysqld_chroot)
     set_root(mysqld_chroot);

sql/set_var.cc

@@ -62,6 +62,12 @@ TYPELIB bool_typelib=
   array_elements(bool_type_names)-1, "", bool_type_names
 };
 
+const char *delay_key_write_type_names[]= { "OFF", "ON", "ALL", NullS };
+TYPELIB delay_key_write_typelib=
+{
+  array_elements(delay_key_write_type_names)-1, "", delay_key_write_type_names
+};
+
 static bool sys_check_charset(THD *thd, set_var *var);
 static bool sys_update_charset(THD *thd, set_var *var);
 static void sys_set_default_charset(THD *thd, enum_var_type type);
@@ -97,8 +103,10 @@ sys_var_bool_ptr	sys_concurrent_insert("concurrent_insert",
 					      &myisam_concurrent_insert);
 sys_var_long_ptr	sys_connect_timeout("connect_timeout",
 					    &connect_timeout);
-sys_var_bool_ptr	sys_delay_key_write("delay_key_write",
-					    &myisam_delay_key_write);
+sys_var_enum		sys_delay_key_write("delay_key_write",
+					    &delay_key_write_options,
+					    &delay_key_write_typelib,
+					    fix_delay_key_write);
 sys_var_long_ptr	sys_delayed_insert_limit("delayed_insert_limit",
 						 &delayed_insert_limit);
 sys_var_long_ptr	sys_delayed_insert_timeout("delayed_insert_timeout",
@@ -625,6 +633,23 @@ static void fix_key_buffer_size(THD *thd, enum_var_type type)
 }
 
 
+void fix_delay_key_write(THD *thd, enum_var_type type)
+{
+  switch ((enum_delay_key_write) delay_key_write_options) {
+  case DELAY_KEY_WRITE_NONE:
+    myisam_delay_key_write=0;
+    break;
+  case DELAY_KEY_WRITE_ON:
+    myisam_delay_key_write=1;
+    break;
+  case DELAY_KEY_WRITE_ALL:
+    myisam_delay_key_write=1;
+    ha_open_options|= HA_OPEN_DELAY_KEY_WRITE;
+    break;
+  }
+}
+
+
 bool sys_var_long_ptr::update(THD *thd, set_var *var)
 {
   ulonglong tmp= var->value->val_int();
@@ -655,6 +680,19 @@ void sys_var_bool_ptr::set_default(THD *thd, enum_var_type type)
 }
 
 
+bool sys_var_enum::update(THD *thd, set_var *var)
+{
+  *value= (uint) var->save_result.ulong_value;
+  return 0;
+}
+
+
+byte *sys_var_enum::value_ptr(THD *thd, enum_var_type type)
+{
+  return (byte*) enum_names->type_names[*value];
+}
+
+
 bool sys_var_thd_ulong::update(THD *thd, set_var *var)
 {
   ulonglong tmp= var->value->val_int();

sql/set_var.h

@@ -28,7 +28,7 @@
 class sys_var;
 class set_var;
 typedef struct system_variables SV;
-extern TYPELIB bool_typelib;
+extern TYPELIB bool_typelib, delay_key_write_typelib;
 
 enum enum_var_type
 {
@@ -140,6 +140,26 @@ class sys_var_str :public sys_var
 };
 
 
+class sys_var_enum :public sys_var
+{
+  uint	*value; 
+  TYPELIB *enum_names;
+public:
+  sys_var_enum(const char *name_arg, uint *value_arg,
+	       TYPELIB *typelib, sys_after_update_func func)
+    :sys_var(name_arg,func), value(value_arg), enum_names(typelib)
+  {}
+  bool check(THD *thd, set_var *var)
+  {
+    return check_enum(thd, var, enum_names);
+  }
+  bool update(THD *thd, set_var *var);
+  SHOW_TYPE type() { return SHOW_CHAR; }
+  byte *value_ptr(THD *thd, enum_var_type type);
+  bool check_update_type(Item_result type) { return 0; }
+};
+
+
 class sys_var_thd :public sys_var
 {
 public:
@@ -415,5 +435,6 @@ void set_var_init();
 void set_var_free();
 sys_var *find_sys_var(const char *str, uint length=0);
 bool sql_set_variables(THD *thd, List<set_var_base> *var_list);
+void fix_delay_key_write(THD *thd, enum_var_type type);
 
 extern sys_var_str sys_charset;

sql/sql_class.h

@@ -31,6 +31,8 @@ enum enum_enable_or_disable { LEAVE_AS_IS, ENABLE, DISABLE };
 enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY };
 enum enum_duplicates { DUP_ERROR, DUP_REPLACE, DUP_IGNORE };
 enum enum_log_type { LOG_CLOSED, LOG_NORMAL, LOG_NEW, LOG_BIN };
+enum enum_delay_key_write { DELAY_KEY_WRITE_NONE, DELAY_KEY_WRITE_ON,
+			    DELAY_KEY_WRITE_ALL };
 
 // log info errors 
 #define LOG_INFO_EOF -1

sql/sql_yacc.yy

@@ -3346,6 +3346,7 @@ set_expr_or_default:
 	expr      { $$=$1; }
 	| DEFAULT { $$=0; }
 	| ON	  { $$=new Item_string("ON",2); }
+	| ALL	  { $$=new Item_string("ALL",3); }
 	;