myisam_data_pointer_size

include/myisam.h

@@ -192,7 +192,7 @@ extern uint myisam_block_size;
 extern my_bool myisam_flush,myisam_delay_key_write,myisam_single_user;
 extern my_bool myisam_concurrent_insert;
 extern my_off_t myisam_max_temp_length,myisam_max_extra_temp_length;
-extern ulong myisam_bulk_insert_tree_size;
+extern ulong myisam_bulk_insert_tree_size, myisam_data_pointer_size;
 
 	/* Prototypes for myisam-functions */
 

include/mysql.h

@@ -120,7 +120,7 @@ typedef unsigned long long my_ulonglong;
 typedef struct st_mysql_rows {
   struct st_mysql_rows *next;		/* list of rows */
   MYSQL_ROW data;
-  ulong	    length;
+  unsigned long length;
 } MYSQL_ROWS;
 
 typedef MYSQL_ROWS *MYSQL_ROW_OFFSET;	/* offset to current row */

myisam/mi_create.c

@@ -206,9 +206,9 @@ int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
 					  3 : 0)));
 
   if (options & (HA_OPTION_COMPRESS_RECORD | HA_OPTION_PACK_RECORD))
-    pointer=mi_get_pointer_length(ci->data_file_length,4);
+    pointer=mi_get_pointer_length(ci->data_file_length,myisam_data_pointer_size);
   else
-    pointer=mi_get_pointer_length(ci->max_rows,4);
+    pointer=mi_get_pointer_length(ci->max_rows,myisam_data_pointer_size);
   if (!(max_rows=(ulonglong) ci->max_rows))
     max_rows= ((((ulonglong) 1 << (pointer*8)) -1) / min_pack_length);
 

myisam/mi_info.c

@@ -75,7 +75,8 @@ int mi_status(MI_INFO *info, register MI_ISAMINFO *x, uint flag)
     x->filenr	 = info->dfile;
     x->options	 = share->options;
     x->create_time=share->state.create_time;
-    x->reflength= mi_get_pointer_length(share->base.max_data_file_length,4);
+    x->reflength= mi_get_pointer_length(share->base.max_data_file_length,
+                                        myisam_data_pointer_size);
     x->record_offset= ((share->options &
 			(HA_OPTION_PACK_RECORD | HA_OPTION_COMPRESS_RECORD)) ?
 		       0L : share->base.pack_reclength);

myisam/mi_static.c

@@ -41,6 +41,7 @@ my_bool myisam_concurrent_insert=0;
 my_off_t myisam_max_extra_temp_length= MI_MAX_TEMP_LENGTH;
 my_off_t myisam_max_temp_length= MAX_FILE_SIZE;
 ulong    myisam_bulk_insert_tree_size=8192*1024;
+ulong    myisam_data_pointer_size=4;
 
 /*
   read_vec[] is used for converting between P_READ_KEY.. and SEARCH_

sql/mysqld.cc

@@ -3661,7 +3661,7 @@ enum options_mysqld
   OPT_MAX_SEEKS_FOR_KEY, OPT_MAX_TMP_TABLES, OPT_MAX_USER_CONNECTIONS,
   OPT_MAX_LENGTH_FOR_SORT_DATA,
   OPT_MAX_WRITE_LOCK_COUNT, OPT_BULK_INSERT_BUFFER_SIZE,
-  OPT_MAX_ERROR_COUNT,
+  OPT_MAX_ERROR_COUNT, OPT_MYISAM_DATA_POINTER_SIZE,
   OPT_MYISAM_BLOCK_SIZE, OPT_MYISAM_MAX_EXTRA_SORT_FILE_SIZE,
   OPT_MYISAM_MAX_SORT_FILE_SIZE, OPT_MYISAM_SORT_BUFFER_SIZE,
   OPT_NET_BUFFER_LENGTH, OPT_NET_RETRY_COUNT,
@@ -4515,6 +4515,11 @@ The minimum value for this variable is 4096.",
    (gptr*) &opt_myisam_block_size, 0, GET_ULONG, REQUIRED_ARG,
    MI_KEY_BLOCK_LENGTH, MI_MIN_KEY_BLOCK_LENGTH, MI_MAX_KEY_BLOCK_LENGTH,
    0, MI_MIN_KEY_BLOCK_LENGTH, 0},
+  {"myisam_data_pointer_size", OPT_MYISAM_DATA_POINTER_SIZE,
+   "Default pointer size to be used for MyISAM tables.",
+   (gptr*) &myisam_data_pointer_size,
+   (gptr*) &myisam_data_pointer_size, 0, GET_ULONG, REQUIRED_ARG,
+   4, 2, 7, 0, 1, 0},
   {"myisam_max_extra_sort_file_size", OPT_MYISAM_MAX_EXTRA_SORT_FILE_SIZE,
    "Used to help MySQL to decide when to use the slow but safe key cache index create method.",
    (gptr*) &global_system_variables.myisam_max_extra_sort_file_size,

sql/set_var.cc

@@ -242,6 +242,8 @@ sys_var_thd_ulong	sys_max_tmp_tables("max_tmp_tables",
 					   &SV::max_tmp_tables);
 sys_var_long_ptr	sys_max_write_lock_count("max_write_lock_count",
 						 &max_write_lock_count);
+sys_var_long_ptr	sys_myisam_data_pointer_size("myisam_data_pointer_size",
+                                                    &myisam_data_pointer_size);
 sys_var_thd_ulonglong	sys_myisam_max_extra_sort_file_size("myisam_max_extra_sort_file_size", &SV::myisam_max_extra_sort_file_size, fix_myisam_max_extra_sort_file_size, 1);
 sys_var_thd_ulonglong	sys_myisam_max_sort_file_size("myisam_max_sort_file_size", &SV::myisam_max_sort_file_size, fix_myisam_max_sort_file_size, 1);
 sys_var_thd_ulong       sys_myisam_repair_threads("myisam_repair_threads", &SV::myisam_repair_threads);
@@ -521,6 +523,7 @@ sys_var *sys_variables[]=
   &sys_max_tmp_tables,
   &sys_max_user_connections,
   &sys_max_write_lock_count,
+  &sys_myisam_data_pointer_size,
   &sys_myisam_max_extra_sort_file_size,
   &sys_myisam_max_sort_file_size,
   &sys_myisam_repair_threads,
@@ -721,6 +724,7 @@ struct show_var_st init_vars[]= {
   {sys_max_tmp_tables.name,	(char*) &sys_max_tmp_tables,	    SHOW_SYS},
   {sys_max_user_connections.name,(char*) &sys_max_user_connections, SHOW_SYS},
   {sys_max_write_lock_count.name, (char*) &sys_max_write_lock_count,SHOW_SYS},
+  {sys_myisam_data_pointer_size.name, (char*) &sys_myisam_data_pointer_size, SHOW_SYS},
   {sys_myisam_max_extra_sort_file_size.name,
    (char*) &sys_myisam_max_extra_sort_file_size,
    SHOW_SYS},