merge

include/my_sys.h

@@ -843,6 +843,8 @@ extern void *memdup_root(MEM_ROOT *root,const void *str, size_t len);
 extern int get_defaults_options(int argc, char **argv,
                                 char **defaults, char **extra_defaults,
                                 char **group_suffix);
+extern int my_load_defaults(const char *conf_file, const char **groups,
+                            int *argc, char ***argv, const char ***);
 extern int load_defaults(const char *conf_file, const char **groups,
                          int *argc, char ***argv);
 extern int modify_defaults_file(const char *file_location, const char *option,
@@ -850,7 +852,8 @@ extern int modify_defaults_file(const char *file_location, const char *option,
                                 const char *section_name, int remove_option);
 extern int my_search_option_files(const char *conf_file, int *argc,
                                   char ***argv, uint *args_used,
-                                  Process_option_func func, void *func_ctx);
+                                  Process_option_func func, void *func_ctx,
+                                  const char **default_directories);
 extern void free_defaults(char **argv);
 extern void my_print_default_files(const char *conf_file);
 extern void print_defaults(const char *conf_file, const char **groups);

mysql-test/r/select.result

@@ -4416,4 +4416,32 @@ date_nokey
 Warnings:
 Warning	1292	Incorrect date value: '10:41:7' for column 'date_nokey' at row 1
 DROP TABLE A,C;
+CREATE TABLE t1 (a INT NOT NULL, b INT);
+INSERT INTO t1 VALUES (1, 1);
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a) OR b > 2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	100.00	
+Warnings:
+Note	1003	select '1' AS `a`,'1' AS `b` from `test`.`t1` where 1
+SELECT * FROM t1 WHERE (a=a AND a=a) OR b > 2;
+a	b
+1	1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT NOT NULL, b INT NOT NULL, c INT NOT NULL);
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND c=c) OR b > 20;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+Warnings:
+Note	1003	select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a AND b=b) OR b > 20;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+Warnings:
+Note	1003	select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND a=a) OR b > 20;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	0.00	const row not found
+Warnings:
+Note	1003	select '0' AS `a`,'0' AS `b`,'0' AS `c` from `test`.`t1` where 1
+DROP TABLE t1;
 End of 5.1 tests

mysql-test/t/select.test

@@ -3769,4 +3769,20 @@ SELECT date_nokey FROM C
 
 DROP TABLE A,C;
 
+#
+# Bug #42957: no results from 
+# select where .. (col=col and col=col) or ... (false expression)
+#
+CREATE TABLE t1 (a INT NOT NULL, b INT);
+INSERT INTO t1 VALUES (1, 1);
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a) OR b > 2;
+SELECT * FROM t1 WHERE (a=a AND a=a) OR b > 2;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT NOT NULL, b INT NOT NULL, c INT NOT NULL);
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND c=c) OR b > 20;
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND a=a AND b=b) OR b > 20;
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (a=a AND b=b AND a=a) OR b > 20;
+DROP TABLE t1;
+
 --echo End of 5.1 tests

mysys/default.c

@@ -152,7 +152,7 @@ static char *remove_end_comment(char *ptr);
 
 int my_search_option_files(const char *conf_file, int *argc, char ***argv,
                            uint *args_used, Process_option_func func,
-                           void *func_ctx)
+                           void *func_ctx, const char **default_directories)
 {
   const char **dirs, *forced_default_file, *forced_extra_defaults;
   int error= 0;
@@ -359,18 +359,46 @@ int get_defaults_options(int argc, char **argv,
   return org_argc - argc;
 }
 
+/*
+  Wrapper around my_load_defaults() for interface compatibility.
+
+  SYNOPSIS
+    load_defaults()
+    conf_file			Basename for configuration file to search for.
+    				If this is a path, then only this file is read.
+    groups			Which [group] entrys to read.
+				Points to an null terminated array of pointers
+    argc			Pointer to argc of original program
+    argv			Pointer to argv of original program
+
+  NOTES
+
+    This function is NOT thread-safe as it uses a global pointer internally.
+    See also notes for my_load_defaults().
+
+  RETURN
+    0 ok
+    1 The given conf_file didn't exists
+*/
+int load_defaults(const char *conf_file, const char **groups,
+                  int *argc, char ***argv)
+{
+  return my_load_defaults(conf_file, groups, argc, argv, &default_directories);
+}
 
 /*
   Read options from configurations files
 
   SYNOPSIS
-    load_defaults()
+    my_load_defaults()
     conf_file			Basename for configuration file to search for.
     				If this is a path, then only this file is read.
     groups			Which [group] entrys to read.
 				Points to an null terminated array of pointers
     argc			Pointer to argc of original program
     argv			Pointer to argv of original program
+    default_directories         Pointer to a location where a pointer to the list
+                                of default directories will be stored
 
   IMPLEMENTATION
 
@@ -386,13 +414,18 @@ int get_defaults_options(int argc, char **argv,
     that was put in *argv
 
    RETURN
-     0	ok
-     1	The given conf_file didn't exists
+     - If successful, 0 is returned. If 'default_directories' is not NULL,
+     a pointer to the array of default directory paths is stored to a location
+     it points to. That stored value must be passed to my_search_option_files()
+     later.
+     
+     - 1 is returned if the given conf_file didn't exist. In this case, the
+     value pointed to by default_directories is undefined.
 */
 
 
-int load_defaults(const char *conf_file, const char **groups,
-                  int *argc, char ***argv)
+int my_load_defaults(const char *conf_file, const char **groups,
+                  int *argc, char ***argv, const char ***default_directories)
 {
   DYNAMIC_ARRAY args;
   TYPELIB group;
@@ -402,10 +435,11 @@ int load_defaults(const char *conf_file, const char **groups,
   MEM_ROOT alloc;
   char *ptr,**res;
   struct handle_option_ctx ctx;
+  const char **dirs;
   DBUG_ENTER("load_defaults");
 
   init_alloc_root(&alloc,512,0);
-  if ((default_directories= init_default_directories(&alloc)) == NULL)
+  if ((dirs= init_default_directories(&alloc)) == NULL)
     goto err;
   /*
     Check if the user doesn't want any default option processing
@@ -426,6 +460,8 @@ int load_defaults(const char *conf_file, const char **groups,
     (*argc)--;
     *argv=res;
     *(MEM_ROOT*) ptr= alloc;			/* Save alloc root for free */
+    if (default_directories)
+      *default_directories= dirs;
     DBUG_RETURN(0);
   }
 
@@ -444,7 +480,8 @@ int load_defaults(const char *conf_file, const char **groups,
   ctx.group= &group;
 
   error= my_search_option_files(conf_file, argc, argv, &args_used,
-                                handle_default_option, (void *) &ctx);
+                                handle_default_option, (void *) &ctx,
+                                dirs);
   /*
     Here error contains <> 0 only if we have a fully specified conf_file
     or a forced default file
@@ -490,6 +527,10 @@ int load_defaults(const char *conf_file, const char **groups,
     puts("");
     exit(0);
   }
+
+  if (error == 0 && default_directories)
+    *default_directories= dirs;
+
   DBUG_RETURN(error);
 
  err:
@@ -895,15 +936,11 @@ void my_print_default_files(const char *conf_file)
     fputs(conf_file,stdout);
   else
   {
-    /*
-      If default_directories is already initialized, use it.  Otherwise,
-      use a private MEM_ROOT.
-    */
-    const char **dirs = default_directories;
+    const char **dirs;
     MEM_ROOT alloc;
     init_alloc_root(&alloc,512,0);
 
-    if (!dirs && (dirs= init_default_directories(&alloc)) == NULL)
+    if ((dirs= init_default_directories(&alloc)) == NULL)
     {
       fputs("Internal error initializing default directories list", stdout);
     }

server-tools/instance-manager/instance_map.cc

@@ -536,7 +536,8 @@ int Instance_map::load()
   */
   if (my_search_option_files(Options::Main::config_file, &argc,
                              (char ***) &argv, &args_used,
-                             process_option, (void*) this))
+                             process_option, (void*) this,
+                             Options::default_directories))
     log_info("Falling back to compiled-in defaults.");
 
   return complete_initialization();

server-tools/instance-manager/options.cc

@@ -86,6 +86,7 @@ const char *Options::Main::bind_address= NULL; /* No default value */
 uint Options::Main::monitoring_interval= DEFAULT_MONITORING_INTERVAL;
 uint Options::Main::port_number= DEFAULT_PORT;
 my_bool Options::Main::mysqld_safe_compatible= FALSE;
+const char **Options::default_directories= NULL;
 
 /* Options::User_management */
 
@@ -439,7 +440,8 @@ int Options::load(int argc, char **argv)
   log_info("Loading config file '%s'...",
            (const char *) Main::config_file);
 
-  load_defaults(Main::config_file, default_groups, &argc, &saved_argv);
+  my_load_defaults(Main::config_file, default_groups, &argc,
+                   &saved_argv, &default_directories);
 
   if ((handle_options(&argc, &saved_argv, my_long_options, get_one_option)))
     return ERR_INVALID_USAGE;

server-tools/instance-manager/options.h

@@ -91,6 +91,9 @@ struct Options
 #endif
 
 public:
+  /* Array of paths to be passed to my_search_option_files() later */
+  static const char **default_directories;
+
   static int load(int argc, char **argv);
   static void cleanup();
 

sql-common/client.c

@@ -1021,7 +1021,7 @@ void mysql_read_default_options(struct st_mysql_options *options,
   argc=1; argv=argv_buff; argv_buff[0]= (char*) "client";
   groups[0]= (char*) "client"; groups[1]= (char*) group; groups[2]=0;
 
-  load_defaults(filename, groups, &argc, &argv);
+  my_load_defaults(filename, groups, &argc, &argv, NULL);
   if (argc != 1)				/* If some default option */
   {
     char **option=argv;

sql/sql_plugin.cc

@@ -1652,7 +1652,7 @@ bool mysql_install_plugin(THD *thd, const LEX_STRING *name, const LEX_STRING *dl
   pthread_mutex_lock(&LOCK_plugin);
   rw_wrlock(&LOCK_system_variables_hash);
 
-  load_defaults(MYSQL_CONFIG_NAME, load_default_groups, &argc, &argv);
+  my_load_defaults(MYSQL_CONFIG_NAME, load_default_groups, &argc, &argv, NULL);
   error= plugin_add(thd->mem_root, name, dl, &argc, argv, REPORT_TO_USER);
   if (argv)
     free_defaults(argv);

sql/sql_select.cc

@@ -7625,7 +7625,7 @@ static COND *build_equal_items_for_cond(THD *thd, COND *cond,
     if (and_level)
     {
       /*
-         Retrieve all conjucts of this level detecting the equality
+         Retrieve all conjuncts of this level detecting the equality
          that are subject to substitution by multiple equality items and
          removing each such predicate from the conjunction after having 
          found/created a multiple equality whose inference the predicate is.
@@ -7641,6 +7641,13 @@ static COND *build_equal_items_for_cond(THD *thd, COND *cond,
           li.remove();
       }
 
+      /*
+        Check if we eliminated all the predicates of the level, e.g.
+        (a=a AND b=b AND a=a)
+      */
+      if (!(args->elements + cond_equal.current_level.elements + eq_list.elements))
+        return new Item_int((longlong) 1,1);
+
       List_iterator_fast<Item_equal> it(cond_equal.current_level);
       while ((item_equal= it++))
       {