From: Date: December 6 2006 7:37pm
Subject: bk commit into 5.0 tree (evgen:1.2320) BUG#16861
List-Archive: http://lists.mysql.com/commits/16538
X-Bug: 16861
Message-Id: <20061206183720.49AE822DB97@moonbone.moonbone.local>

Below is the list of changes that have just been committed into a local
5.0 repository of evgen. When evgen does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet@stripped, 2006-12-06 21:37:16+03:00, evgen@stripped +4 -0
  Fixed bug#16861: User defined variable can have a wrong value if a tmp table was
  used.
  
  The Item::save_in_field() function is called from fill_record() to fill fields 
  with data for a new row in a CREATE TABLE ... SELECT statement.
  It calls val_xxx() methods in order to get values. Due to this
  Item_func_set_user_var object returns values from the original table, not from
  a temporary one.
  
  The save_in_field() member function is added to the Item_func_set_user_var
  class. It detects when the result field should be used and uses it in such
  cases.

  mysql-test/r/user_var.result@stripped, 2006-12-06 21:04:16+03:00, evgen@stripped +8 -1
    Extended the test case for bug#18681: User defined variable can have a wrong value if a tmp table was used.

  mysql-test/t/user_var.test@stripped, 2006-12-06 21:03:34+03:00, evgen@stripped +4 -1
    Extended the test case for bug#18681: User defined variable can have a wrong value if a tmp table was
    used.

  sql/item_func.cc@stripped, 2006-12-06 21:09:13+03:00, evgen@stripped +64 -0
    Bug#16861: User defined variable can have a wrong value if a tmp table was used.
    Added the save_in_field() member function to the Item_func_set_user_var class.

  sql/item_func.h@stripped, 2006-12-06 21:06:45+03:00, evgen@stripped +1 -0
    Bug#16861: User defined variable can have a wrong value if a tmp table was used.
    Added the save_in_field() member function to the Item_func_set_user_var class.

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	evgen
# Host:	moonbone.local
# Root:	/work/16861-bug-5.0-opt-mysql

--- 1.315/sql/item_func.cc	2006-12-04 15:25:41 +03:00
+++ 1.316/sql/item_func.cc	2006-12-06 21:09:13 +03:00
@@ -4040,6 +4040,70 @@
     Item::make_field(tmp_field);
 }
 
+int Item_func_set_user_var::save_in_field(Field *field, bool no_conversions)
+{
+  bool use_result_field= (result_field && result_field != field);
+  int error;
+
+  if (use_result_field)
+  {
+    check(1);
+    update();
+  }
+  if (result_type() == STRING_RESULT ||
+      result_type() == REAL_RESULT &&
+      field->result_type() == STRING_RESULT)
+  {
+    String *result;
+    CHARSET_INFO *cs= collation.collation;
+    char buff[MAX_FIELD_WIDTH];		// Alloc buffer for small columns
+    str_value.set_quick(buff, sizeof(buff), cs);
+    result= use_result_field ?
+              entry->val_str(&null_value, &str_value, decimals) :
+              val_str(&str_value);
+    if (null_value)
+    {
+      str_value.set_quick(0, 0, cs);
+      return set_field_to_null_with_conversions(field, no_conversions);
+    }
+
+    /* NOTE: If null_value == FALSE, "result" must be not NULL.  */
+
+    field->set_notnull();
+    error=field->store(result->ptr(),result->length(),cs);
+    str_value.set_quick(0, 0, cs);
+  }
+  else if (result_type() == REAL_RESULT)
+  {
+    double nr= use_result_field ? entry->val_real(&null_value) : val_real();
+    if (null_value)
+      return set_field_to_null(field);
+    field->set_notnull();
+    error=field->store(nr);
+  }
+  else if (result_type() == DECIMAL_RESULT)
+  {
+    my_decimal decimal_value;
+    my_decimal *value=
+      use_result_field ? entry->val_decimal(&null_value, &decimal_value) :
+                                            val_decimal(&decimal_value);
+    if (null_value)
+      return set_field_to_null(field);
+    field->set_notnull();
+    error=field->store_decimal(value);
+  }
+  else
+  {
+    longlong nr= use_result_field ? entry->val_int(&null_value) : val_int();
+    if (null_value)
+      return set_field_to_null_with_conversions(field, no_conversions);
+    field->set_notnull();
+    error=field->store(nr, unsigned_flag);
+  }
+  return error;
+}
+
+
 String *
 Item_func_get_user_var::val_str(String *str)
 {

--- 1.160/sql/item_func.h	2006-11-28 16:47:47 +03:00
+++ 1.161/sql/item_func.h	2006-12-06 21:06:45 +03:00
@@ -1189,6 +1189,7 @@
   void print(String *str);
   void print_as_stmt(String *str);
   const char *func_name() const { return "set_user_var"; }
+  int save_in_field(Field *field, bool no_conversions);
 };
 
 

--- 1.43/mysql-test/r/user_var.result	2006-10-04 18:49:37 +04:00
+++ 1.44/mysql-test/r/user_var.result	2006-12-06 21:04:16 +03:00
@@ -301,7 +301,14 @@
 select @var;
 @var
 3
-drop table t1;
+create table t2 as select @var:=f2 from t1 group by f1 order by f2 desc limit 1;
+select * from t2;
+@var:=f2
+3
+select @var;
+@var
+3
+drop table t1,t2;
 insert into city 'blah';
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''blah'' at line 1
 SHOW COUNT(*) WARNINGS;

--- 1.38/mysql-test/t/user_var.test	2006-10-04 18:49:37 +04:00
+++ 1.39/mysql-test/t/user_var.test	2006-12-06 21:03:34 +03:00
@@ -210,7 +210,10 @@
 insert into t1 values (1,2),(2,3),(3,1);
 select @var:=f2 from t1 group by f1 order by f2 desc limit 1;
 select @var;
-drop table t1;
+create table t2 as select @var:=f2 from t1 group by f1 order by f2 desc limit 1;
+select * from t2;
+select @var;
+drop table t1,t2;
 
 #
 # Bug#19024 - SHOW COUNT(*) WARNINGS not return Errors