Write UNION() for MERGE tables

Docs/manual.texi:
  Clearify when logging is done
myisam/myisamchk.c:
  Better error message
mysql-test/r/merge.result:
  Added test for SHOW CREATE on MERGE table
scripts/safe_mysqld.sh:
  Search by default in database directory
sql/ha_myisammrg.h:
  Add UNION() to SHOW CREATE TABLE
sql/sql_update.cc:
  removed compiler warning

Docs/manual.texi

@@ -22747,6 +22747,10 @@ that can be used as one.  You can only @code{SELECT}, @code{DELETE}, and
 @code{MERGE} table, you are only dropping the @code{MERGE}
 specification.
 
+Note that @code{DELETE FROM merge_table} used without a @code{WHERE}
+will only clear the mapping for the table, not delete everything in the
+mapped tables. (We plan to fix this in 4.0).
+
 With identical tables we mean that all tables are created with identical
 column information.  You can't put a MERGE over tables where the columns
 are packed differently or doesn't have exactly the same columns.
@@ -35114,6 +35118,17 @@ to the log file (by default named 'hostname.log').  This log can
 be very useful when you suspect an error in a client and want to know
 exactly what @code{mysqld} thought the client send to it.
 
+By default, the @code{mysql.server} script starts the @strong{MySQL}
+server with the @code{-l} option.  If you need better performance when
+you start using @strong{MySQL} in a production environment, you can
+remove the @code{-l} option from @code{mysql.server} or change it to
+@code{--log-binary}.
+
+The entries in this log are written as @code{mysqld} receives the questions.
+This may be different than the order in which the statements is executed.
+This is in contrast to the update log and the binary log which is written
+after the query is executed, but before any locks are released.
+
 @cindex update log
 @cindex files, update log
 @node Update log, Binary log, Query log, Log files
@@ -35149,17 +35164,15 @@ cp hostname-old.log to-backup-directory
 rm hostname-old.log
 @end example
 
-By default, the @code{mysql.server} script starts the @strong{MySQL}
-server with the @code{-l} option.  If you need better performance when
-you start using @strong{MySQL} in a production environment, you can
-remove the @code{-l} option from @code{mysql.server} or change it to
-@code{--log-update}.
-
 Update logging is smart because it logs only statements that really update
 data. So an @code{UPDATE} or a @code{DELETE} with a @code{WHERE} that finds no
 rows is not written to the log. It even skips @code{UPDATE} statements that
 set a column to the value it already has.
 
+The update logging is done immediately after a query completes but before
+any locks are released or any commit is done. This ensures that the log
+will be logged in the execution order.
+
 If you want to update a database from update log files, you could do the
 following (assuming your update logs have names of the form
 @file{file_name.###}):
@@ -35229,6 +35242,10 @@ this program!
 If you are using @code{BEGIN} or @code{SET AUTO_COMMIT=0}, you must use
 the @strong{MySQL} binary log for backups instead of the old update log.
 
+The binary logging is done immediately after a query completes but before
+any locks are released or any commit is done. This ensures that the log
+will be logged in the execution order.
+
 All updates (@code{UPDATE}, @code{DELETE} or @code{INSERT}) that changes
 a transactional table (like BDB tables) is cached until a @code{COMMIT}.
 Any updates to a not transactional table is stored in the binary log at
@@ -35250,6 +35267,10 @@ When started with the @code{--log-slow-queries[=file_name]} option,
 more than @code{long_query_time} to execute. The time to get the initial
 table locks are not counted as execution time.
 
+The slow query log is logged after the query is executed and after all
+locks has been released. This may be different than the order in which
+the statements is executed.
+
 If no file name is given, it defaults to the name of the host machine
 suffixed with @code{-slow.log}. If a filename is given, but doesn't
 contain a path, the file is written in the data directory.
@@ -41421,6 +41442,12 @@ not yet 100 % confident in this code.
 @appendixsubsec Changes in release 3.23.34
 @itemize @bullet
 @item
+@code{SHOW CREATE TABLE} now dumps the @code{UNION()} for @code{MERGE} tables.
+@item
+Fixed bug when replicating timestamps.
+@item
+Fixed bug in bi-directonal replication.
+@item
 Added the @code{INNOBASE} table handler and the @code{BDB} table handler
 to the @strong{MySQL} source distribution.
 @item
@@ -46205,6 +46232,10 @@ For the moment @code{MATCH} only works with @code{SELECT} statements.
 When using @code{SET CHARACTER SET}, one can't use translated
 characters in database, table and column names.
 @item
+@code{DELETE FROM merge_table} used without a @code{WHERE}
+will only clear the mapping for the table, not delete everything in the
+mapped tables
+@item
 You cannot build in another directory when using
 MIT-pthreads. Because this requires changes to MIT-pthreads, we are not
 likely to fix this.

myisam/myisamchk.c

@@ -860,7 +860,7 @@ end2:
 		   filename));
       if (check_param.testflag & (T_REP_BY_SORT | T_REP))
 	VOID(fprintf(stderr,
-		     "Try fixing it by using the --safe-recover (-o) option\n"));
+		     "Try fixing it by using the --safe-recover (-o) or the --force (-f) option\n"));
     }
     else if (!(param->error_printed & 2) &&
 	     !(param->testflag & T_FORCE_CREATE))

mysql-test/r/merge.result

@@ -81,6 +81,12 @@ a
 412
 412
 411
+Table	Create Table
+t3	CREATE TABLE `t3` (
+  `a` int(11) NOT NULL default '0',
+  `b` char(20) default NULL,
+  KEY `a` (`a`)
+) TYPE=MRG_MyISAM UNION=(t1,t2)
 c
 test1
 test1

scripts/safe_mysqld.sh

@@ -72,6 +72,10 @@ then
   MY_BASEDIR_VERSION=$MY_PWD		# Where bin, share and data are
   ledir=$MY_BASEDIR_VERSION/bin		# Where mysqld is
   DATADIR=$MY_BASEDIR_VERSION/data
+  if test -z "defaults"
+  then
+    defaults="--defaults-extra-file=$MY_BASEDIR_VERSION/data/my.cnf"
+  fi
 # Check if this is a 'moved install directory'
 elif test -f ./var/mysql/db.frm -a -f ./share/mysql/english/errmsg.sys -a \
  -x ./libexec/mysqld

sql/ha_myisammrg.cc

@@ -238,3 +238,20 @@ int ha_myisammrg::create(const char *name, register TABLE *form,
   DBUG_RETURN(myrg_create(fn_format(buff,name,"","",2+4+16),
 			  (const char **) table_names, (my_bool) 0));
 }
+
+void ha_myisammrg::append_create_info(String *packet)
+{
+  char buff[FN_REFLEN];
+  packet->append(" UNION=(",8);
+  MYRG_TABLE *table,*first;
+
+  for (first=table=file->open_tables ; table != file->end_table ; table++)
+  {
+    char *name=table->table->s->filename;
+    fn_format(buff,name,"","",3);
+    if (table != first)
+      packet->append(',');
+    packet->append(buff,(uint) strlen(buff));
+  }
+  packet->append(')');
+}

sql/ha_myisammrg.h

@@ -72,4 +72,5 @@ class ha_myisammrg: public handler
   int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info);
   THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to,
 			     enum thr_lock_type lock_type);
+  void append_create_info(String *packet);
 };

sql/sql_update.cc

@@ -59,6 +59,7 @@ int mysql_update(THD *thd,TABLE_LIST *table_list,List<Item> &fields,
   READ_RECORD	info;
   DBUG_ENTER("mysql_update");
   LINT_INIT(used_index);
+  LINT_INIT(timestamp_query_id);
 
   if (!(table = open_ltable(thd,table_list,lock_type)))
     DBUG_RETURN(-1);