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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.
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ChangeSet@stripped, 2006-12-14 23:40:50+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 the
new row with a data while the CREATE TABLE ... SELECT statement.
Item::save_in_field() calls val_xxx() methods in order to get values.
val_xxx() methods do not take into account the result field. 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 properly updates
the value of the user variable.
mysql-test/r/user_var.result@stripped, 2006-12-14 23:33:01+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, 2006-12-14 23:33:06+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, 2006-12-14 23:32:47+03:00, evgen@stripped +99 -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, 2006-12-14 23:32:56+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 2006-12-14 23:32:47 +03:00
@@ -4040,6 +4040,105 @@
Item::make_field(tmp_field);
}
+
+/*
+ Save the value of a user variable into a field
+
+ SYNOPSIS
+ save_in_field()
+ field target field to save the value to
+ no_conversion flag indicating whether a conversions are allowed
+
+ DESCRIPTION
+ Save the function value into a field and update the user variable
+ accordingly. If a result field is define and the target field doesn't
+ coincide with it then the value from the result field will be used as
+ the new value of the user variable.
+
+ The reason to have this method rather than simply using the result
+ field in the val_xxx() methods is that the value from the result field
+ not always can be used when the result field is defined.
+ Let's consider the following examples:
+ 1) when filling a tmp table the result field is defined but the value of it
+ is undefined because it has to be produced yet. Thus we can't use it.
+ 2) on execution of an INSERT ... SELECT statement the save_in_field()
+ function will be called to fill the data in the new record. If the SELECT
+ part uses a tmp table then the result field is defined and should be
+ used in order to get a correct result.
+
+ The difference between the SET_USER_VAR function and regular functions
+ like CONCAT is that the Item_func objects for the regular functions are
+ replaced by Item_field objects after the values of these functions have
+ been stored in a tmp table. Yet an object of the Item_field class cannot
+ be used to update a user variable.
+ Due to this we have to handle the result field in a special way here and
+ in the Item_func_set_user_var::send() function.
+
+ RETURN VALUES
+ FALSE Ok
+ TRUE Error
+*/
+
+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;
+
+ /* Update the value of the user variable */
+ check(use_result_field);
+ 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= entry->val_str(&null_value, &str_value, decimals);
+
+ 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= entry->val_real(&null_value);
+ 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= entry->val_decimal(&null_value, &decimal_value);
+ if (null_value)
+ return set_field_to_null(field);
+ field->set_notnull();
+ error=field->store_decimal(value);
+ }
+ else
+ {
+ longlong nr= entry->val_int(&null_value);
+ 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 2006-12-14 23:32:56 +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 2006-12-14 23:33:01 +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 2006-12-14 23:33:06 +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
| Thread |
|---|
| • bk commit into 5.0 tree (evgen:1.2320) BUG#16861 | eugene | 14 Dec |
