Merge tulin@bk-internal.mysql.com:/home/bk/mysql-5.0

into poseidon.ndb.mysql.com:/home/tomas/mysql-5.1-clean


BitKeeper/etc/logging_ok:
  auto-union
configure.in:
  Auto merged
sql/ha_innodb.cc:
  Auto merged
sql/ha_myisam.cc:
  Auto merged
sql/ha_myisammrg.cc:
  Auto merged
sql/lock.cc:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_repl.cc:
  Auto merged
storage/heap/hp_hash.c:
  Auto merged
storage/innobase/dict/dict0dict.c:
  Auto merged
storage/innobase/fil/fil0fil.c:
  Auto merged
storage/innobase/include/dict0dict.h:
  Auto merged
storage/myisam/Makefile.am:
  Auto merged
storage/myisam/mi_key.c:
  Auto merged
storage/myisam/myisampack.c:
  Auto merged
storage/myisammrg/myrg_open.c:
  Auto merged
storage/ndb/include/ndbapi/NdbDictionary.hpp:
  Auto merged
storage/ndb/src/ndbapi/NdbDictionaryImpl.cpp:
  Auto merged
storage/ndb/src/ndbapi/ndberror.c:
  Auto merged

1 files changed, 33 insertions, 5 deletions

diff --git a/sql/ha_myisammrg.cc b/sql/ha_myisammrg.cc
index 1d86e31054e..71f0564c82b 100644
--- a/sql/ha_myisammrg.cc
+++ b/sql/ha_myisammrg.cc
@@ -32,8 +32,16 @@
 ** MyISAM MERGE tables
 *****************************************************************************/
 
+static const char *ha_myisammrg_exts[] = {
+  ".MRG",
+  NullS
+};
+
 const char **ha_myisammrg::bas_ext() const
-{ static const char *ext[]= { ".MRG", NullS }; return ext; }
+{
+  return ha_myisammrg_exts;
+}
+
 
 const char *ha_myisammrg::index_type(uint key_number)
 {
@@ -392,6 +400,7 @@ int ha_myisammrg::create(const char *name, register TABLE *form,
   const char **table_names, **pos;
   TABLE_LIST *tables= (TABLE_LIST*) create_info->merge_list.first;
   THD *thd= current_thd;
+  uint dirlgt= dirname_length(name);
   DBUG_ENTER("ha_myisammrg::create");
 
   if (!(table_names= (const char**)
@@ -405,11 +414,30 @@ int ha_myisammrg::create(const char *name, register TABLE *form,
       tbl= find_temporary_table(thd, tables->db, tables->table_name);
     if (!tbl)
     {
-      uint length= my_snprintf(buff,FN_REFLEN,"%s%s/%s",
-			       mysql_real_data_home,
+      /*
+        Construct the path to the MyISAM table. Try to meet two conditions:
+        1.) Allow to include MyISAM tables from different databases, and
+        2.) allow for moving DATADIR around in the file system.
+        The first means that we need paths in the .MRG file. The second
+        means that we should not have absolute paths in the .MRG file.
+        The best, we can do, is to use 'mysql_data_home', which is '.'
+        in mysqld and may be an absolute path in an embedded server.
+        This means that it might not be possible to move the DATADIR of
+        an embedded server without changing the paths in the .MRG file.
+      */
+      uint length= my_snprintf(buff, FN_REFLEN, "%s/%s/%s", mysql_data_home,
 			       tables->db, tables->table_name);
-      if (!(table_name= thd->strmake(buff, length)))
-	DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+      /*
+        If a MyISAM table is in the same directory as the MERGE table,
+        we use the table name without a path. This means that the
+        DATADIR can easily be moved even for an embedded server as long
+        as the MyISAM tables are from the same database as the MERGE table.
+      */
+      if ((dirname_length(buff) == dirlgt) && ! memcmp(buff, name, dirlgt))
+        table_name= tables->table_name;
+      else
+        if (! (table_name= thd->strmake(buff, length)))
+          DBUG_RETURN(HA_ERR_OUT_OF_MEM);
     }
     else
       table_name= (*tbl)->s->path;