mirror of
https://github.com/MariaDB/server.git
synced 2025-01-19 13:32:33 +01:00
a4d840a09c
Added test cases for bug #7351. item_cmpfunc.cc: Fixed bug #7351: incorrect result for a query with a subquery returning empty set. If in the predicate v IN (SELECT a FROM t WHERE cond) v is null, then the result of the predicate is either INKNOWN or FALSE. It is FALSE if the subquery returns an empty set. item_subselect.cc: Fixed bug #7351: incorrect result for a query with a subquery returning empty set. The problem was due to not a quite legal transformation for 'IN' subqueries. A subquery containing a predicate of the form v IN (SELECT a FROM t WHERE cond) was transformed into EXISTS(SELECT a FROM t WHERE cond AND (a=v OR a IS NULL)). Yet, this transformation is valid only if v is not null. If v is null, then, in the case when (SELECT a FROM t WHERE cond) returns an empty set the value of the predicate is FALSE, otherwise the result of the predicate is INKNOWN. The fix resolves this problem by changing the result of the transformation to EXISTS(SELECT a FROM t WHERE cond AND (v IS NULL OR (a=v OR a IS NULL))) in the case when v is nullable. The new transformation prevents applying the lookup optimization for IN subqueries. To make it still applicable we have to introduce guarded access methods. sql/item_subselect.cc: Fixed bug #7351: incorrect result for a query with a subquery returning empty set. The problem was due to not a quite legal transformation for 'IN' subqueries. A subquery containing a predicate of the form v IN (SELECT a FROM t WHERE cond) was transformed into EXISTS(SELECT a FROM t WHERE cond AND (a=v OR a IS NULL)). Yet, this transformation is valid only if v is not null. If v is null, then, in the case when (SELECT a FROM t WHERE cond) returns an empty set the value of the predicate is FALSE, otherwise the result of the predicate is INKNOWN. The fix resolves this problem by changing the result of the transformation to EXISTS(SELECT a FROM t WHERE cond AND (v IS NULL OR (a=v OR a IS NULL))) in the case when v is nullable. The new transformation prevents applying the lookup optimization for IN subqueries. To make it still applicable we have to introduce guarded access methods. sql/item_cmpfunc.cc: Fixed bug #7351: incorrect result for a query with a subquery returning empty set. If in the predicate v IN (SELECT a FROM t WHERE cond) v is null, then the result of the predicate is either INKNOWN or FALSE. It is FALSE if the subquery returns an empty set. mysql-test/t/subselect.test: Added test cases for bug #7351. mysql-test/r/subselect.result: Added test cases for bug #7351. |
||
---|---|---|
.. | ||
include | ||
misc | ||
ndb | ||
r | ||
std_data | ||
t | ||
create-test-result | ||
fix-result | ||
init_db.sql | ||
install_test_db.sh | ||
Makefile.am | ||
my_create_tables.c | ||
my_manage.c | ||
my_manage.h | ||
mysql-test-run.sh | ||
mysql_test_run_new.c | ||
README | ||
README.gcov | ||
resolve-stack |
This directory contains a test suite for mysql daemon. To run the currently existing test cases, simply execute ./mysql-test-run in this directory. It will fire up the newly built mysqld and test it. If you want to run the test with a running MySQL server use the --external option to mysql-test-run. Note that you do not have to have to do make install, and you could actually have a co-existing MySQL installation - the tests will not conflict with it. All tests must pass. If one or more of them fail on your system, please read the following manual section of how to report the problem: http://dev.mysql.com/doc/mysql/en/MySQL_test_suite.html You can create your own test cases. To create a test case: xeamacs t/test_case_name.test in the file, put a set of SQL commands that will create some tables, load test data, run some queries to manipulate it. We would appreciate if the test tables were called t1, t2, t3 ... (to not conflict too much with existing tables). Your test should begin by dropping the tables you are going to create and end by dropping them again. This will ensure that one can run the test over and over again. If you are using mysqltest commands (like result file names) in your test case you should do create the result file as follows: mysql-test-run --record test_case_name or mysqltest --record < t/test_case_name.test If you only have a simple test cases consistent of SQL commands and comments you can create the test case one of the following ways: mysql-test-run --record test_case_name mysql test < t/test_case_name.test > r/test_case_name.result mysqltest --record --record-file=r/test_case_name.result < t/test_case_name.test When this is done, take a look at r/test_case_name.result - If the result is wrong, you have found a bug; In this case you should edit the test result to the correct results so that we can verify that the bug is corrected in future releases. To submit your test case, put your .test file and .result file(s) into a tar.gz archive, add a README that explains the problem, ftp the archive to ftp://support.mysql.com/pub/mysql/secret/ and send a mail to bugs@lists.mysql.com