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Bug#11756928 48916: SERVER INCORRECTLY PROCESSING HAVING CLAUSES WITH AN ORDER BY CLAUSE

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Before sorting HAVING condition is split into two parts,
first part is a table related condition and the rest of is
HAVING part. Extraction of HAVING part does not take into account
the fact that some of conditions might be non-const but
have 'used_tables' == 0 (independent subqueries)
and because of that these conditions are cut off by
make_cond_for_table() function.
The fix is to use (table_map) 0 instead of used_tables in
third argument for make_cond_for_table() function.
It allows to extract elements which belong to sorted
table and in addition elements which are independend
subqueries.


mysql-test/r/having.result:
  test case
mysql-test/t/having.test:
  test case
sql/sql_select.cc:
  The fix is to use (table_map) 0 instead of used_tables in
  third argument for make_cond_for_table() function.
  It allows to extract elements which belong to sorted
  table and in addition elements which are independend
  subqueries.
This commit is contained in:
Sergey Glukhov
2011-04-22 11:20:55 +04:00
parent f3b024cafa
commit a5e8d9029b
3 changed files with 85 additions and 1 deletions
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38
sql/sql_select.cc
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@ -2215,7 +2215,7 @@ JOIN::exec()
Item* sort_table_cond= make_cond_for_table(curr_join->tmp_having,
used_tables,
used_tables);
(table_map) 0);
if (sort_table_cond)
{
if (!curr_table->select)
@ -12852,6 +12852,42 @@ static bool test_if_ref(Item_field *left_item,Item *right_item)
return 0; // keep test
}
/**
Extract a condition that can be checked after reading given table
@param cond Condition to analyze
@param tables Tables for which "current field values" are available
@param used_table Table that we're extracting the condition for (may
also include PSEUDO_TABLE_BITS, and may be zero)
@param exclude_expensive_cond Do not push expensive conditions
@retval <>NULL Generated condition
@retval =NULL Already checked, OR error
@details
Extract the condition that can be checked after reading the table
specified in 'used_table', given that current-field values for tables
specified in 'tables' bitmap are available.
If 'used_table' is 0
- extract conditions for all tables in 'tables'.
- extract conditions are unrelated to any tables
in the same query block/level(i.e. conditions
which have used_tables == 0).
The function assumes that
- Constant parts of the condition has already been checked.
- Condition that could be checked for tables in 'tables' has already
been checked.
The function takes into account that some parts of the condition are
guaranteed to be true by employed 'ref' access methods (the code that
does this is located at the end, search down for "EQ_FUNC").
@note
Make sure to keep the implementations of make_cond_for_table() and
make_cond_after_sjm() synchronized.
make_cond_for_info_schema() uses similar algorithm as well.
*/
static COND *
make_cond_for_table(COND *cond, table_map tables, table_map used_table)