From c66208cfbf2726a2c9fe6eed9f4d71e2fff5dfbd Mon Sep 17 00:00:00 2001
From: unknown <monty@hundin.mysql.fi>
Date: Tue, 18 Sep 2001 22:13:35 +0300
Subject: [PATCH] Fix bug in SELECT EXPLAIN ... ORDER BY

Docs/internals.texi:
  Added more code style suggestions.
Docs/manual.texi:
  Changelog
myisam/mi_check.c:
  Removed dbug info
---
 Docs/internals.texi | 52 +++++++++++++++++++++++++++++++++++++++++++--
 Docs/manual.texi    |  3 +++
 myisam/mi_check.c   |  6 ------
 sql/sql_select.cc   | 11 ++++++----
 4 files changed, 60 insertions(+), 12 deletions(-)

diff --git a/Docs/internals.texi b/Docs/internals.texi
index e0574df550b..2195b42d9a0 100644
--- a/Docs/internals.texi
+++ b/Docs/internals.texi
@@ -214,12 +214,15 @@ you will not develop sloppy coding habits.
 If you can write it in fewer lines, do it (as long as the code will not
 be slower or much harder to read).
 
+@item
+Don't use two commands on the same line.
+
 @item
 Do not check the same pointer for @code{NULL} more than once.
 
 @item
-Use long function and variable names in English;  This makes your
-code easier to read.
+Use long function and variable names in English; This makes your code
+easier to read.  Use the 'varible_name' style instead of 'VariableName'.
 
 @item
 Think assembly - make it easier for the compiler to optimize your code.
@@ -266,6 +269,25 @@ Any @code{#define}'s are in all-caps.
 @item
 Matching @samp{@{} are in the same column.
 
+@item
+Put the @samp{@{} after a 'switch' on the same line
+
+@example
+switch (arg) {
+@end example
+
+Because this gives better overall indentation for the switch statement.
+
+@item
+In all other cases, @{ and @} should be on their own line, except
+if there is nothing inside @{ @}.
+
+@item
+Have a space after 'if'
+
+@item
+Put a space after ',' for function arguments
+
 @item
 Functions return 0 on success, and non-zero on error, so you can do:
 
@@ -289,6 +311,32 @@ Use pointers rather than array indexing when operating on strings.
 
 @end itemize
 
+Suggested mode in emacs:
+
+@example
+(load "cc-mode")
+(setq c-mode-common-hook '(lambda ()
+			    (turn-on-font-lock)
+			    (setq comment-column 48)))
+(setq c-style-alist
+      (cons
+       '("MY"
+	 (c-basic-offset . 2)
+	 (c-comment-only-line-offset . 0)
+	 (c-offsets-alist . ((statement-block-intro . +)
+			     (knr-argdecl-intro . 0)
+			     (substatement-open . 0)
+			     (label . -)
+			     (statement-cont . +)
+			     (arglist-intro . c-lineup-arglist-intro-after-paren)
+			     (arglist-close . c-lineup-arglist)
+			     ))
+	 )
+       c-style-alist))
+(c-set-style "MY")
+(setq c-default-style "MY")
+@end example
+
 @node mysys functions,,,
 @chapter mysys functions
 
diff --git a/Docs/manual.texi b/Docs/manual.texi
index 9cf7f74feff..6dd44a79288 100644
--- a/Docs/manual.texi
+++ b/Docs/manual.texi
@@ -46853,6 +46853,9 @@ not yet 100% confident in this code.
 @appendixsubsec Changes in release 3.23.43
 @itemize @bullet
 @item
+Fixed a unlikely core-dump bug when doing @code{EXPLAIN SELECT} when using
+many tables and @code{ORDER BY}.
+@item
 Fixed bug in @code{LOAD DATA FROM MASTER} when using table with
 @code{CHECKSUM=1}.
 @item
diff --git a/myisam/mi_check.c b/myisam/mi_check.c
index c4f37511ffa..fa4687e27f5 100644
--- a/myisam/mi_check.c
+++ b/myisam/mi_check.c
@@ -1291,10 +1291,7 @@ int mi_repair(MI_CHECK *param, register MI_INFO *info,
   {
     info->state->data_file_length=sort_info->max_pos;
     if (param->testflag & T_CALC_CHECKSUM)
-    {
-      DBUG_PRINT("QQ",("set_checksum"));
       share->state.checksum=param->glob_crc;
-    }
   }
 
   if (!(param->testflag & T_SILENT))
@@ -2136,10 +2133,7 @@ static int sort_get_next_record(SORT_INFO *sort_info)
       if (*sort_info->record)
       {
 	if (param->calc_checksum)
-	{
-	  DBUG_PRINT("QQ",("calc_checksum"));
 	  param->glob_crc+= mi_static_checksum(info,sort_info->record);
-	}
 	DBUG_RETURN(0);
       }
       if (!sort_info->fix_datafile)
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index b6c261d1463..56ba4baed30 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -531,8 +531,9 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds,
 
   if (!(select_options & SELECT_BIG_RESULT) &&
       ((group && join.const_tables != join.tables &&
-	!test_if_skip_sort_order(&join.join_tab[join.const_tables], group,
-				 HA_POS_ERROR)) ||
+	(!simple_group ||
+	 !test_if_skip_sort_order(&join.join_tab[join.const_tables], group,
+				  HA_POS_ERROR))) ||
        select_distinct) &&
       join.tmp_table_param.quick_group && !procedure)
   {
@@ -545,8 +546,10 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds,
       order=group;
     if (order &&
 	(join.const_tables == join.tables ||
-	 test_if_skip_sort_order(&join.join_tab[join.const_tables], order,
-				 (group ? HA_POS_ERROR : thd->select_limit))))
+	 (simple_order &&
+	  test_if_skip_sort_order(&join.join_tab[join.const_tables], order,
+				  (group ? HA_POS_ERROR :
+				   thd->select_limit)))))
       order=0;
     select_describe(&join,need_tmp,
 		    (order != 0 &&