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Bug#41371 Select returns 1 row with condition "col is not null and col is null"

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For application compatibility reasons  MySQL converts "<autoincrement_column> IS NULL"
    predicates to "<autoincrement_column> = LAST_INSERT_ID()" in the first SELECT following an
    INSERT regardless of whether they're top level predicates or not. This causes wrong and
    obscure results when these predicates are combined with others on the same columns. Fixed
    by only doing the transformation on a single top-level predicate if a special SQL mode is
    turned on (sql_auto_is_null).
    Also made sql_auto_is_null off by default.

per-file comments:
  mysql-test/r/func_isnull.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
    test result updated

  mysql-test/t/func_isnull.test
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
    test case added

  sql/mysqld.cc
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
    sql_auto_is_null now is OFF by default.

  sql/sql_select.cc
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
    remove_eq_conds() split in two parts - one only checks the upper condition,
    the req_remove_eq_conds() recursively checks all the condition tree.

  mysql-test/extra/rpl_tests/rpl_insert_id.test
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        test fixed (set the sql_auto_is_null variable)

  mysql-test/r/mysqlbinlog.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/r/mysqlbinlog2.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/r/odbc.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/r/query_cache.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/r/user_var-binlog.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/suite/binlog/r/binlog_row_ctype_ucs.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/suite/binlog/r/binlog_stm_ctype_ucs.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/suite/rpl/r/rpl_insert_id.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/suite/rpl/r/rpl_row_mysqlbinlog.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/suite/rpl/r/rpl_sp.result
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        result updated

  mysql-test/t/odbc.test
Bug#41371      Select returns 1 row with condition "col is not null and col is null"
        test fixed (set the sql_auto_is_null variable)
This commit is contained in:
Alexey Botchkov
2009-11-03 17:54:41 +04:00
parent 40536582fc
commit 567bf9d37c
16 changed files with 185 additions and 107 deletions
Download Patch File Download Diff File Expand all files Collapse all files

154
sql/sql_select.cc
View File

@ -9119,18 +9119,26 @@ optimize_cond(JOIN *join, COND *conds, List<TABLE_LIST> *join_list,
/**
Remove const and eq items.
Handles the reqursive job for remove_eq_conds()
@return
Return new item, or NULL if no condition @n
cond_value is set to according:
- COND_OK : query is possible (field = constant)
- COND_TRUE : always true ( 1 = 1 )
- COND_FALSE : always false ( 1 = 2 )
Remove const and eq items. Return new item, or NULL if no condition
cond_value is set to according:
COND_OK query is possible (field = constant)
COND_TRUE always true ( 1 = 1 )
COND_FALSE always false ( 1 = 2 )
SYNPOSIS
remove_eq_conds()
thd THD environment
cond the condition to handle
cond_value the resulting value of the condition
RETURN
*COND with the simplified condition
*/
COND *
remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
static COND *
internal_remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
{
if (cond->type() == Item::COND_ITEM)
{
@ -9144,7 +9152,7 @@ remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
Item *item;
while ((item=li++))
{
Item *new_item=remove_eq_conds(thd, item, &tmp_cond_value);
Item *new_item=internal_remove_eq_conds(thd, item, &tmp_cond_value);
if (!new_item)
li.remove();
else if (item != new_item)
@ -9192,6 +9200,86 @@ remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
}
else if (cond->type() == Item::FUNC_ITEM &&
((Item_func*) cond)->functype() == Item_func::ISNULL_FUNC)
{
Item_func_isnull *func=(Item_func_isnull*) cond;
Item **args= func->arguments();
if (args[0]->type() == Item::FIELD_ITEM)
{
Field *field=((Item_field*) args[0])->field;
/* fix to replace 'NULL' dates with '0' (shreeve@uci.edu) */
/*
datetime_field IS NULL has to be modified to
datetime_field == 0
*/
if (((field->type() == MYSQL_TYPE_DATE) ||
(field->type() == MYSQL_TYPE_DATETIME)) &&
(field->flags & NOT_NULL_FLAG) && !field->table->maybe_null)
{
COND *new_cond;
if ((new_cond= new Item_func_eq(args[0],new Item_int("0", 0, 2))))
{
cond=new_cond;
/*
Item_func_eq can't be fixed after creation so we do not check
cond->fixed, also it do not need tables so we use 0 as second
argument.
*/
cond->fix_fields(thd, &cond);
}
}
}
if (cond->const_item())
{
*cond_value= eval_const_cond(cond) ? Item::COND_TRUE : Item::COND_FALSE;
return (COND*) 0;
}
}
else if (cond->const_item())
{
*cond_value= eval_const_cond(cond) ? Item::COND_TRUE : Item::COND_FALSE;
return (COND*) 0;
}
else if ((*cond_value= cond->eq_cmp_result()) != Item::COND_OK)
{ // boolan compare function
Item *left_item= ((Item_func*) cond)->arguments()[0];
Item *right_item= ((Item_func*) cond)->arguments()[1];
if (left_item->eq(right_item,1))
{
if (!left_item->maybe_null ||
((Item_func*) cond)->functype() == Item_func::EQUAL_FUNC)
return (COND*) 0; // Compare of identical items
}
}
*cond_value=Item::COND_OK;
return cond; // Point at next and level
}
/**
Remove const and eq items. Return new item, or NULL if no condition
cond_value is set to according:
COND_OK query is possible (field = constant)
COND_TRUE always true ( 1 = 1 )
COND_FALSE always false ( 1 = 2 )
SYNPOSIS
remove_eq_conds()
thd THD environment
cond the condition to handle
cond_value the resulting value of the condition
NOTES
calls the inner_remove_eq_conds to check all the tree reqursively
RETURN
*COND with the simplified condition
*/
COND *
remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
{
if (cond->type() == Item::FUNC_ITEM &&
((Item_func*) cond)->functype() == Item_func::ISNULL_FUNC)
{
/*
Handles this special case for some ODBC applications:
@ -9235,52 +9323,16 @@ remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
clear for next row
*/
thd->substitute_null_with_insert_id= FALSE;
}
/* fix to replace 'NULL' dates with '0' (shreeve@uci.edu) */
else if (((field->type() == MYSQL_TYPE_DATE) ||
(field->type() == MYSQL_TYPE_DATETIME)) &&
(field->flags & NOT_NULL_FLAG) &&
!field->table->maybe_null)
{
COND *new_cond;
if ((new_cond= new Item_func_eq(args[0],new Item_int("0", 0, 2))))
{
cond=new_cond;
/*
Item_func_eq can't be fixed after creation so we do not check
cond->fixed, also it do not need tables so we use 0 as second
argument.
*/
cond->fix_fields(thd, &cond);
}
*cond_value= Item::COND_OK;
return cond;
}
}
if (cond->const_item())
{
*cond_value= eval_const_cond(cond) ? Item::COND_TRUE : Item::COND_FALSE;
return (COND*) 0;
}
}
else if (cond->const_item())
{
*cond_value= eval_const_cond(cond) ? Item::COND_TRUE : Item::COND_FALSE;
return (COND*) 0;
}
else if ((*cond_value= cond->eq_cmp_result()) != Item::COND_OK)
{ // boolan compare function
Item *left_item= ((Item_func*) cond)->arguments()[0];
Item *right_item= ((Item_func*) cond)->arguments()[1];
if (left_item->eq(right_item,1))
{
if (!left_item->maybe_null ||
((Item_func*) cond)->functype() == Item_func::EQUAL_FUNC)
return (COND*) 0; // Compare of identical items
}
}
*cond_value=Item::COND_OK;
return cond; // Point at next and level
return internal_remove_eq_conds(thd, cond, cond_value); // Scan all the condition
}
/*
Check if equality can be used in removing components of GROUP BY/DISTINCT