Merge bk@192.168.21.1:mysql-4.1

into  mysql.com:/home/hf/work/mysql-4.1-mrg

Makefile.am

@@ -125,7 +125,9 @@ test-force-pl:
 	./mysql-test-run.pl --force && \
 	./mysql-test-run.pl --ps-protocol --force
 
-test-force-pl-mem:
+#used by autopush.pl to run memory based tests
+test-force-mem:
 	cd mysql-test; \
 	./mysql-test-run.pl --force --mem && \
 	./mysql-test-run.pl --ps-protocol --force --mem
+

client/mysqltest.c

@@ -29,6 +29,7 @@
   Matt Wagner  <matt@mysql.com>
   Monty
   Jani
+  Holyfoot
 */
 
 #define MTEST_VERSION "3.0"
@@ -182,6 +183,18 @@ DYNAMIC_ARRAY q_lines;
 
 #include "sslopt-vars.h"
 
+struct connection
+{
+  MYSQL mysql;
+  char *name;
+
+  const char *cur_query;
+  int cur_query_len;
+  pthread_mutex_t mutex;
+  pthread_cond_t cond;
+  int query_done;
+};
+
 struct
 {
   int read_lines,current_line;
@@ -459,7 +472,6 @@ void mysql_disable_rpl_parse(MYSQL* mysql __attribute__((unused))) {}
 int mysql_rpl_parse_enabled(MYSQL* mysql __attribute__((unused))) { return 1; }
 my_bool mysql_rpl_probe(MYSQL *mysql __attribute__((unused))) { return 1; }
 #endif
-
 void replace_dynstr_append_mem(DYNAMIC_STRING *ds, const char *val,
                                int len);
 void replace_dynstr_append(DYNAMIC_STRING *ds, const char *val);
@@ -471,6 +483,56 @@ void handle_error(struct st_command*,
 void handle_no_error(struct st_command*);
 
 
+#ifdef EMBEDDED_LIBRARY
+/*
+  send_one_query executes query in separate thread what is
+  necessary in embedded library to run 'send' in proper way.
+  This implementation doesn't handle errors returned
+  by mysql_send_query. It's technically possible, though
+  i don't see where it is needed.
+*/
+pthread_handler_decl(send_one_query, arg)
+{
+  struct connection *cn= (struct connection*)arg;
+
+  mysql_thread_init();
+  VOID(mysql_send_query(&cn->mysql, cn->cur_query, cn->cur_query_len));
+
+  mysql_thread_end();
+  pthread_mutex_lock(&cn->mutex);
+  cn->query_done= 1;
+  VOID(pthread_cond_signal(&cn->cond));
+  pthread_mutex_unlock(&cn->mutex);
+  pthread_exit(0);
+  return 0;
+}
+
+static int do_send_query(struct connection *cn, const char *q, int q_len,
+                         int flags)
+{
+  pthread_t tid;
+
+  if (flags & QUERY_REAP_FLAG)
+    return mysql_send_query(&cn->mysql, q, q_len);
+
+  if (pthread_mutex_init(&cn->mutex, NULL) ||
+      pthread_cond_init(&cn->cond, NULL))
+    die("Error in the thread library");
+
+  cn->cur_query= q;
+  cn->cur_query_len= q_len;
+  cn->query_done= 0;
+  if (pthread_create(&tid, NULL, send_one_query, (void*)cn))
+    die("Cannot start new thread for query");
+
+  return 0;
+}
+
+#else /*EMBEDDED_LIBRARY*/
+
+#define do_send_query(cn,q,q_len,flags) mysql_send_query(&cn->mysql, q, q_len)
+
+#endif /*EMBEDDED_LIBRARY*/
 
 void do_eval(DYNAMIC_STRING *query_eval, const char *query,
              const char *query_end, my_bool pass_through_escape_chars)
@@ -4492,7 +4554,6 @@ int append_warnings(DYNAMIC_STRING *ds, MYSQL* mysql)
 }
 
 
-
 /*
   Run query using MySQL C API
 
@@ -4509,10 +4570,11 @@ int append_warnings(DYNAMIC_STRING *ds, MYSQL* mysql)
   error - function will not return
 */
 
-void run_query_normal(MYSQL *mysql, struct st_command *command,
+void run_query_normal(struct connection *cn, *mysql, struct st_command *command,
                       int flags, char *query, int query_len,
                       DYNAMIC_STRING *ds, DYNAMIC_STRING *ds_warnings)
 {
+  MYSQL *mysql= &cn->mysql;
   MYSQL_RES *res= 0;
   int err= 0, counter= 0;
   DBUG_ENTER("run_query_normal");
@@ -4524,14 +4586,26 @@ void run_query_normal(MYSQL *mysql, struct st_command *command,
     /*
       Send the query
     */
-    if (mysql_send_query(mysql, query, query_len))
+    if (do_send_query(cn, query, query_len, flags))
     {
       handle_error(command, mysql_errno(mysql), mysql_error(mysql),
 		   mysql_sqlstate(mysql), ds);
       goto end;
     }
   }
-
+#ifdef EMBEDDED_LIBRARY
+  /*
+   Here we handle 'reap' command, so we need to check if the
+   query's thread was finished and probably wait
+  */
+  else if (flags & QUERY_REAP)
+  {
+    pthread_mutex_lock(&cn->mutex);
+    while (!cn->query_done)
+      pthread_cond_wait(&cn->cond, &cn->mutex);
+    pthread_mutex_unlock(&cn->mutex);
+  }
+#endif /*EMBEDDED_LIBRARY*/
   if (!(flags & QUERY_REAP_FLAG))
     DBUG_VOID_RETURN;
 
@@ -5641,7 +5715,7 @@ int main(int argc, char **argv)
 	  strmake(command->require_file, save_file, sizeof(save_file));
 	  save_file[0]= 0;
 	}
-	run_query(&cur_con->mysql, command, QUERY_REAP_FLAG|QUERY_SEND_FLAG);
+	run_query(cur_con, command, QUERY_REAP_FLAG|QUERY_SEND_FLAG);
 	display_result_vertically= old_display_result_vertically;
         command->last_argument= command->end;
         command_executed++;
@@ -5672,7 +5746,7 @@ int main(int argc, char **argv)
 	  strmake(command->require_file, save_file, sizeof(save_file));
 	  save_file[0]= 0;
 	}
-	run_query(&cur_con->mysql, command, flags);
+	run_query(cur, command, flags);
 	command_executed++;
         command->last_argument= command->end;
 	break;
@@ -5698,7 +5772,7 @@ int main(int argc, char **argv)
           the query and read the result some time later when reap instruction
 	  is given on this connection.
         */
-	run_query(&cur_con->mysql, command, QUERY_SEND_FLAG);
+	run_query(cur_con, command, QUERY_SEND_FLAG);
 	command_executed++;
         command->last_argument= command->end;
 	break;

include/mysql.h

@@ -281,12 +281,6 @@ typedef struct st_mysql
     from mysql_stmt_close if close had to cancel result set of this object.
   */
   my_bool *unbuffered_fetch_owner;
-  /*
-    In embedded server it points to the statement that is processed
-    in the current query. We store some results directly in statement
-    fields then.
-  */
-  struct st_mysql_stmt *current_stmt;
 } MYSQL;
 
 typedef struct st_mysql_res {

libmysql/libmysql.c

@@ -4395,13 +4395,6 @@ int STDCALL mysql_stmt_store_result(MYSQL_STMT *stmt)
     set_stmt_error(stmt, CR_COMMANDS_OUT_OF_SYNC, unknown_sqlstate);
     DBUG_RETURN(1);
   }
-  if (result->data)
-  {
-    free_root(&result->alloc, MYF(MY_KEEP_PREALLOC));
-    result->data= NULL;
-    result->rows= 0;
-    stmt->data_cursor= NULL;
-  }
 
   if (stmt->update_max_length && !stmt->bind_result_done)
   {

libmysqld/lib_sql.cc

@@ -94,7 +94,7 @@ emb_advanced_command(MYSQL *mysql, enum enum_server_command command,
   mysql->affected_rows= ~(my_ulonglong) 0;
   mysql->field_count= 0;
   net->last_errno= 0;
-  mysql->current_stmt= stmt;
+  thd->current_stmt= stmt;
 
   thd->store_globals();				// Fix if more than one connect
   /* 
@@ -644,8 +644,8 @@ bool Protocol::send_fields(List<Item> *list, uint flag)
     DBUG_RETURN(0);
 
   field_count= list->elements;
-  field_alloc= mysql->current_stmt ? &mysql->current_stmt->mem_root :
-                                     &mysql->field_alloc;
+  field_alloc= thd->current_stmt ? &thd->current_stmt->mem_root :
+                                   &mysql->field_alloc;
   if (!(client_field= mysql->fields= 
 	(MYSQL_FIELD *)alloc_root(field_alloc, 
 				  sizeof(MYSQL_FIELD) * field_count)))
@@ -751,8 +751,8 @@ bool Protocol_prep::write()
   {
     MYSQL *mysql= thd->mysql;
 
-    if (mysql->current_stmt)
-      data= &mysql->current_stmt->result;
+    if (thd->current_stmt)
+      data= &thd->current_stmt->result;
     else
     {
       if (!(data= (MYSQL_DATA*) my_malloc(sizeof(MYSQL_DATA),

mysql-test/r/order_by.result

@@ -820,3 +820,30 @@ b	a
 20	1
 10	2
 DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1),(2);
+SELECT a + 1 AS num FROM t1 ORDER BY 30 - num;
+num
+3
+2
+SELECT CONCAT('test', a) AS str FROM t1 ORDER BY UPPER(str);
+str
+test1
+test2
+SELECT a + 1 AS num FROM t1 GROUP BY 30 - num;
+num
+3
+2
+SELECT a + 1 AS num FROM t1 HAVING 30 - num;
+num
+2
+3
+SELECT a + 1 AS num, num + 1 FROM t1;
+ERROR 42S22: Unknown column 'num' in 'field list'
+SELECT a + 1 AS num, (select num + 2 FROM t1 LIMIT 1) FROM t1;
+num	(select num + 2 FROM t1 LIMIT 1)
+2	4
+3	5
+SELECT a.a + 1 AS num FROM t1 a JOIN t1 b ON num = b.a;
+ERROR 42S22: Unknown column 'num' in 'on clause'
+DROP TABLE t1;

mysql-test/r/subselect.result

@@ -2981,3 +2981,35 @@ field1	field2
 1	1
 1	3
 DROP TABLE t1, t2;
+CREATE TABLE t1(a int, INDEX (a));
+INSERT INTO t1 VALUES (1), (3), (5), (7);
+INSERT INTO t1 VALUES (NULL);
+CREATE TABLE t2(a int);
+INSERT INTO t2 VALUES (1),(2),(3);
+EXPLAIN SELECT a, a IN (SELECT a FROM t1) FROM t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	3	
+2	DEPENDENT SUBQUERY	t1	index_subquery	a	a	5	func	2	Using index
+SELECT a, a IN (SELECT a FROM t1) FROM t2;
+a	a IN (SELECT a FROM t1)
+1	1
+2	NULL
+3	1
+DROP TABLE t1,t2;
+CREATE TABLE t1 (a DATETIME);
+INSERT INTO t1 VALUES ('1998-09-23'), ('2003-03-25');
+CREATE TABLE t2 AS SELECT 
+(SELECT a FROM t1 WHERE a < '2000-01-01') AS sub_a 
+FROM t1 WHERE a > '2000-01-01';
+SHOW CREATE TABLE t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `sub_a` datetime default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+CREATE TABLE t3 AS (SELECT a FROM t1 WHERE a < '2000-01-01') UNION (SELECT a FROM t1 WHERE a > '2000-01-01');
+SHOW CREATE TABLE t3;
+Table	Create Table
+t3	CREATE TABLE `t3` (
+  `a` datetime default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+DROP TABLE t1,t2,t3;

mysql-test/t/bdb-deadlock.test

-# This test doesn't work with the embedded version as this code
-# assumes that one query is running while we are doing queries on
-# a second connection.
-# This would work if mysqltest run would be threaded and handle each
-# connection in a separate thread.
-#
-
--- source include/not_embedded.inc
 -- source include/have_bdb.inc
 
 connect (con1,localhost,root,,);

mysql-test/t/flush.test

-# This test doesn't work with the embedded version as this code
-# assumes that one query is running while we are doing queries on
-# a second connection.
-# This would work if mysqltest run would be threaded and handle each
-# connection in a separate thread.
-#
--- source include/not_embedded.inc
-
 connect (con1,localhost,root,,);
 connect (con2,localhost,root,,);
 connection con1;

mysql-test/t/flush_block_commit.test

@@ -3,9 +3,6 @@
 # We verify that we did not introduce a deadlock.
 # This is intended to mimick how mysqldump and innobackup work.
 
-# This test doesn't work with the embedded server
--- source include/not_embedded.inc
-
 # And it requires InnoDB
 -- source include/have_innodb.inc
 

mysql-test/t/innodb-deadlock.test

 -- source include/have_innodb.inc
-# Can't test this with embedded server
--- source include/not_embedded.inc
 
 connect (con1,localhost,root,,);
 connect (con2,localhost,root,,);

mysql-test/t/innodb-lock.test

 -- source include/have_innodb.inc
-# Can't test this with embedded server
--- source include/not_embedded.inc
 
 #
 # Check and select innodb lock type

mysql-test/t/lock_multi.test

-# This test doesn't work with the embedded version as this code
-# assumes that one query is running while we are doing queries on
-# a second connection.
-# This would work if mysqltest run would be threaded and handle each
-# connection in a separate thread.
-#
--- source include/not_embedded.inc
-
 --disable_warnings
 drop table if exists t1,t2;
 --enable_warnings

mysql-test/t/mysql_client.test

@@ -34,6 +34,24 @@
 --exec echo 'help' | $MYSQL   >  $MYSQLTEST_VARDIR/tmp/bug20328.tmp
 --exec echo 'help ' | $MYSQL  >  $MYSQLTEST_VARDIR/tmp/bug20328.tmp
 
+#
+# Bug #19216: Client crashes on long SELECT
+#
+--exec echo "select" > $MYSQLTEST_VARDIR/tmp/b19216.tmp
+# 3400 * 20 makes 68000 columns that is more than the max number that can fit 
+# in a 16 bit number.
+let $i= 3400;
+while ($i)
+{
+  --exec echo "'a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a'," >> $MYSQLTEST_VARDIR/tmp/b19216.tmp
+  dec $i;
+}
+
+--exec echo "'b';" >> $MYSQLTEST_VARDIR/tmp/b19216.tmp
+--disable_query_log
+--exec $MYSQL < $MYSQLTEST_VARDIR/tmp/b19216.tmp >/dev/null
+--enable_query_log
+
 #
 # Bug#17583: mysql drops connection when stdout is not writable
 #
@@ -51,4 +69,21 @@ select count(*) from t17583;
 --exec echo "select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; select count(*) from t17583; " |$MYSQL test >&-
 drop table t17583;
 
+#
+# Bug #19216: Client crashes on long SELECT
+#
+--exec echo "select" > $MYSQLTEST_VARDIR/tmp/b19216.tmp
+# 3400 * 20 makes 68000 columns that is more than the max number that can fit 
+# in a 16 bit number.
+let $i= 3400;
+while ($i)
+{
+  --exec echo "'a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a','a'," >> $MYSQLTEST_VARDIR/tmp/b19216.tmp
+  dec $i;
+}
+
+--exec echo "'b';" >> $MYSQLTEST_VARDIR/tmp/b19216.tmp
+--disable_query_log
+--exec $MYSQL < $MYSQLTEST_VARDIR/tmp/b19216.tmp >/dev/null
+--enable_query_log
 --echo End of 4.1 tests.

mysql-test/t/order_by.test

@@ -559,4 +559,20 @@ INSERT INTO t1 VALUES (1,30), (2,20), (1,10), (2,30), (1,20), (2,10);
 
 DROP TABLE t1;
 
+#
+# Bug #22457: Column alias in ORDER BY works, but not if in an expression
+#
+
+CREATE TABLE t1 (a INT); INSERT INTO t1 VALUES (1),(2);
+SELECT a + 1 AS num FROM t1 ORDER BY 30 - num;
+SELECT CONCAT('test', a) AS str FROM t1 ORDER BY UPPER(str);
+SELECT a + 1 AS num FROM t1 GROUP BY 30 - num;
+SELECT a + 1 AS num FROM t1 HAVING 30 - num;
+--error 1054
+SELECT a + 1 AS num, num + 1 FROM t1;
+SELECT a + 1 AS num, (select num + 2 FROM t1 LIMIT 1) FROM t1;
+--error 1054
+SELECT a.a + 1 AS num FROM t1 a JOIN t1 b ON num = b.a;
+DROP TABLE t1;
+
 # End of 4.1 tests

mysql-test/t/rename.test

@@ -2,10 +2,6 @@
 # Test of rename table
 #
 
-# Test requires concurrent connections, which can't be tested on embedded
-# server
--- source include/not_embedded.inc
-
 --disable_warnings
 drop table if exists t0,t1,t2,t3,t4;
 # Clear up from other tests (to ensure that SHOW TABLES below is right)

mysql-test/t/show_check.test

-# Requires use of multiple simultaneous connections, not supported with
-# embedded server testing
+# Uses GRANT commands that usually disabled in embedded server
 -- source include/not_embedded.inc
 
 #

mysql-test/t/status.test

-# This test doesn't work with the embedded version as this code
-# assumes that one query is running while we are doing queries on
-# a second connection.
-# This would work if mysqltest run would be threaded and handle each
-# connection in a separate thread.
-#
---source include/not_embedded.inc
 # PS causes different statistics
 --disable_ps_protocol
 

mysql-test/t/subselect.test

@@ -1948,4 +1948,37 @@ SELECT field1, field2
 
 DROP TABLE t1, t2;
 
+#
+# Bug #23478: not top-level IN subquery returning a non-empty result set
+#             with possible NULL values by index access from the outer query
+#
+
+CREATE TABLE t1(a int, INDEX (a));
+INSERT INTO t1 VALUES (1), (3), (5), (7);
+INSERT INTO t1 VALUES (NULL);
+
+CREATE TABLE t2(a int);
+INSERT INTO t2 VALUES (1),(2),(3);
+
+EXPLAIN SELECT a, a IN (SELECT a FROM t1) FROM t2;
+SELECT a, a IN (SELECT a FROM t1) FROM t2;
+
+DROP TABLE t1,t2;
+
+#
+# Bug #11302: getObject() returns a String for a sub-query of type datetime
+#
+CREATE TABLE t1 (a DATETIME);
+INSERT INTO t1 VALUES ('1998-09-23'), ('2003-03-25');
+
+CREATE TABLE t2 AS SELECT 
+  (SELECT a FROM t1 WHERE a < '2000-01-01') AS sub_a 
+   FROM t1 WHERE a > '2000-01-01';
+SHOW CREATE TABLE t2;
+
+CREATE TABLE t3 AS (SELECT a FROM t1 WHERE a < '2000-01-01') UNION (SELECT a FROM t1 WHERE a > '2000-01-01'); 
+SHOW CREATE TABLE t3;
+
+DROP TABLE t1,t2,t3;
+
 # End of 4.1 tests

sql-common/client.c

@@ -1173,6 +1173,8 @@ unpack_fields(MYSQL_DATA *data,MEM_ROOT *alloc,uint fields,
     for (row=data->data; row ; row = row->next,field++)
     {
       uchar *pos;
+      /* fields count may be wrong */
+      DBUG_ASSERT ((field - result) < fields);
       cli_fetch_lengths(&lengths[0], row->data, default_value ? 8 : 7);
       field->catalog  = strdup_root(alloc,(char*) row->data[0]);
       field->db       = strdup_root(alloc,(char*) row->data[1]);

sql/item.cc

@@ -1761,10 +1761,37 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
         Item** res= find_item_in_list(this, thd->lex->current_select->item_list,
                                       &counter, REPORT_EXCEPT_NOT_FOUND,
                                       &not_used);
-        if (res != (Item **)not_found_item && (*res)->type() == Item::FIELD_ITEM)
+        if (res != (Item **)not_found_item)
         {
-          set_field((*((Item_field**)res))->field);
-          return 0;
+          if ((*res)->type() == Item::FIELD_ITEM)
+          {
+            /*
+             It's an Item_field referencing another Item_field in the select
+             list.
+             use the field from the Item_field in the select list and leave
+             the Item_field instance in place.
+            */
+            set_field((*((Item_field**)res))->field);
+            return 0;
+          }
+          else
+          {
+            /*
+              It's not an Item_field in the select list so we must make a new
+              Item_ref to point to the Item in the select list and replace the
+              Item_field created by the parser with the new Item_ref.
+            */
+            Item_ref *rf= new Item_ref(db_name,table_name,field_name);
+            if (!rf)
+              return 1;
+            thd->change_item_tree(ref, rf);
+            /*
+              Because Item_ref never substitutes itself with other items 
+              in Item_ref::fix_fields(), we can safely use the original 
+              pointer to it even after fix_fields()
+             */
+            return rf->fix_fields(thd, tables, ref) ||  rf->check_cols(1);
+          }
         }
       }
 

sql/item_subselect.cc

@@ -391,6 +391,15 @@ enum Item_result Item_singlerow_subselect::result_type() const
   return engine->type();
 }
 
+/* 
+ Don't rely on the result type to calculate field type. 
+ Ask the engine instead.
+*/
+enum_field_types Item_singlerow_subselect::field_type() const
+{
+  return engine->field_type();
+}
+
 void Item_singlerow_subselect::fix_length_and_dec()
 {
   if ((max_columns= engine->cols()) == 1)
@@ -610,6 +619,7 @@ double Item_in_subselect::val()
   */
   DBUG_ASSERT(0);
   DBUG_ASSERT(fixed == 1);
+  null_value= 0;
   if (exec())
   {
     reset();
@@ -625,6 +635,7 @@ double Item_in_subselect::val()
 longlong Item_in_subselect::val_int()
 {
   DBUG_ASSERT(fixed == 1);
+  null_value= 0;
   if (exec())
   {
     reset();
@@ -645,6 +656,7 @@ String *Item_in_subselect::val_str(String *str)
   */
   DBUG_ASSERT(0);
   DBUG_ASSERT(fixed == 1);
+  null_value= 0;
   if (exec())
   {
     reset();
@@ -1354,31 +1366,35 @@ int subselect_uniquesubquery_engine::prepare()
   return 1;
 }
 
-static Item_result set_row(List<Item> &item_list, Item *item,
-			   Item_cache **row, bool *maybe_null)
+/* 
+ makes storage for the output values for the subquery and calcuates 
+ their data and column types and their nullability.
+*/ 
+void subselect_engine::set_row(List<Item> &item_list, Item_cache **row)
 {
-  Item_result res_type= STRING_RESULT;
   Item *sel_item;
   List_iterator_fast<Item> li(item_list);
+  res_type= STRING_RESULT;
+  res_field_type= FIELD_TYPE_VAR_STRING;
   for (uint i= 0; (sel_item= li++); i++)
   {
     item->max_length= sel_item->max_length;
     res_type= sel_item->result_type();
+    res_field_type= sel_item->field_type();
     item->decimals= sel_item->decimals;
-    *maybe_null= sel_item->maybe_null;
+    maybe_null= sel_item->maybe_null;
     if (!(row[i]= Item_cache::get_cache(res_type)))
-      return STRING_RESULT; // we should return something
+      return;
     row[i]->setup(sel_item);
   }
   if (item_list.elements > 1)
     res_type= ROW_RESULT;
-  return res_type;
 }
 
 void subselect_single_select_engine::fix_length_and_dec(Item_cache **row)
 {
   DBUG_ASSERT(row || select_lex->item_list.elements==1);
-  res_type= set_row(select_lex->item_list, item, row, &maybe_null);
+  set_row(select_lex->item_list, row);
   item->collation.set(row[0]->collation);
   if (cols() != 1)
     maybe_null= 0;
@@ -1390,13 +1406,14 @@ void subselect_union_engine::fix_length_and_dec(Item_cache **row)
 
   if (unit->first_select()->item_list.elements == 1)
   {
-    res_type= set_row(unit->types, item, row, &maybe_null);
+    set_row(unit->types, row);
     item->collation.set(row[0]->collation);
   }
   else
   {
-    bool fake= 0;
-    res_type= set_row(unit->types, item, row, &fake);
+    bool maybe_null_saved= maybe_null;
+    set_row(unit->types, row);
+    maybe_null= maybe_null_saved;
   }
 }
 

sql/item_subselect.h

@@ -142,6 +142,7 @@ public:
   longlong val_int ();
   String *val_str (String *);
   enum Item_result result_type() const;
+  enum_field_types field_type() const;
   void fix_length_and_dec();
 
   uint cols();
@@ -273,6 +274,7 @@ protected:
   THD *thd; /* pointer to current THD */
   Item_subselect *item; /* item, that use this engine */
   enum Item_result res_type; /* type of results */
+  enum_field_types res_field_type; /* column type of the results */
   bool maybe_null; /* may be null (first item in select) */
 public:
 
@@ -282,6 +284,7 @@ public:
     result= res;
     item= si;
     res_type= STRING_RESULT;
+    res_field_type= FIELD_TYPE_VAR_STRING;
     maybe_null= 0;
   }
   virtual ~subselect_engine() {}; // to satisfy compiler
@@ -296,6 +299,7 @@ public:
   virtual uint cols()= 0; /* return number of columnss in select */
   virtual uint8 uncacheable()= 0; /* query is uncacheable */
   enum Item_result type() { return res_type; }
+  enum_field_types field_type() { return res_field_type; }
   virtual void exclude()= 0;
   bool may_be_null() { return maybe_null; };
   virtual table_map upper_select_const_tables()= 0;
@@ -303,6 +307,9 @@ public:
   virtual void print(String *str)= 0;
   virtual int change_item(Item_subselect *si, select_subselect *result)= 0;
   virtual bool no_tables()= 0;
+
+protected:
+  void set_row(List<Item> &item_list, Item_cache **row);
 };
 
 

sql/protocol.cc

@@ -43,7 +43,7 @@ bool Protocol_prep::net_store_data(const char *from, uint length)
       packet->realloc(packet_length+9+length))
     return 1;
   char *to=(char*) net_store_length((char*) packet->ptr()+packet_length,
-				    (ulonglong) length);
+				    length);
   memcpy(to,from,length);
   packet->length((uint) (to+length-packet->ptr()));
   return 0;
@@ -297,8 +297,8 @@ send_ok(THD *thd, ha_rows affected_rows, ulonglong id, const char *message)
     DBUG_VOID_RETURN;
 
   buff[0]=0;					// No fields
-  pos=net_store_length(buff+1,(ulonglong) affected_rows);
-  pos=net_store_length(pos, (ulonglong) id);
+  pos=net_store_length(buff+1,affected_rows);
+  pos=net_store_length(pos, id);
   if (thd->client_capabilities & CLIENT_PROTOCOL_41)
   {
     DBUG_PRINT("info",
@@ -416,7 +416,7 @@ bool send_old_password_request(THD *thd)
   ulonglong for bigger numbers.
 */
 
-char *net_store_length(char *pkg, uint length)
+static char *net_store_length_fast(char *pkg, uint length)
 {
   uchar *packet=(uchar*) pkg;
   if (length < 251)
@@ -439,7 +439,7 @@ char *net_store_length(char *pkg, uint length)
 
 char *net_store_data(char *to,const char *from, uint length)
 {
-  to=net_store_length(to,length);
+  to=net_store_length_fast(to,length);
   memcpy(to,from,length);
   return to+length;
 }
@@ -448,7 +448,7 @@ char *net_store_data(char *to,int32 from)
 {
   char buff[20];
   uint length=(uint) (int10_to_str(from,buff,10)-buff);
-  to=net_store_length(to,length);
+  to=net_store_length_fast(to,length);
   memcpy(to,buff,length);
   return to+length;
 }
@@ -457,7 +457,7 @@ char *net_store_data(char *to,longlong from)
 {
   char buff[22];
   uint length=(uint) (longlong10_to_str(from,buff,10)-buff);
-  to=net_store_length(to,length);
+  to=net_store_length_fast(to,length);
   memcpy(to,buff,length);
   return to+length;
 }
@@ -520,7 +520,7 @@ bool Protocol::send_fields(List<Item> *list, uint flag)
 
   if (flag & 1)
   {				// Packet with number of elements
-    char *pos=net_store_length(buff, (uint) list->elements);
+    char *pos=net_store_length(buff, list->elements);
     (void) my_net_write(&thd->net, buff,(uint) (pos-buff));
   }
 
@@ -648,7 +648,7 @@ bool Protocol::send_records_num(List<Item> *list, ulonglong records)
 {
   char *pos;
   char buff[20];
-  pos=net_store_length(buff, (uint) list->elements);
+  pos=net_store_length(buff, list->elements);
   pos=net_store_length(pos, records);
   return my_net_write(&thd->net, buff,(uint) (pos-buff));
 }

sql/protocol.h

@@ -177,7 +177,6 @@ void send_ok(THD *thd, ha_rows affected_rows=0L, ulonglong id=0L,
 	     const char *info=0);
 void send_eof(THD *thd, bool no_flush=0);
 bool send_old_password_request(THD *thd);
-char *net_store_length(char *packet,uint length);
 char *net_store_data(char *to,const char *from, uint length);
 char *net_store_data(char *to,int32 from);
 char *net_store_data(char *to,longlong from);

sql/sql_class.h

@@ -686,6 +686,12 @@ public:
   char *extra_data;
   ulong extra_length;
   String query_rest;
+  /*
+    In embedded server it points to the statement that is processed
+    in the current query. We store some results directly in statement
+    fields then.
+  */
+  struct st_mysql_stmt *current_stmt;
 #endif
   NET	  net;				// client connection descriptor
   MEM_ROOT warn_root;			// For warnings and errors