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In the code that converts IN predicates to EXISTS predicates it is changing the select list elements to constant 1. Example : SELECT ... FROM ... WHERE a IN (SELECT c FROM ...) is transformed to : SELECT ... FROM ... WHERE EXISTS (SELECT 1 FROM ... HAVING a = c) However there can be no FROM clause in the IN subquery and it may not be a simple select : SELECT ... FROM ... WHERE a IN (SELECT f(..) AS c UNION SELECT ...) This query is transformed to : SELECT ... FROM ... WHERE EXISTS (SELECT 1 FROM (SELECT f(..) AS c UNION SELECT ...) x HAVING a = c) In the above query c in the HAVING clause is made to be an Item_null_helper (a subclass of Item_ref) pointing to the real Item_field (which is not referenced anywhere else in the query anymore). This is done because Item_ref_null_helper collects information whether there are NULL values in the result. This is OK for directly executed statements, because the Item_field pointed by the Item_null_helper is already fixed when the transformation is done. But when executed as a prepared statement all the Item instances are "un-fixed" before the recompilation of the prepared statement. So when the Item_null_helper gets fixed it discovers that the Item_field it points to is not fixed and issues an error. The remedy is to keep the original select list references when there are no tables in the FROM clause. So the above becomes : SELECT ... FROM ... WHERE EXISTS (SELECT c FROM (SELECT f(..) AS c UNION SELECT ...) x HAVING a = c) In this way c is referenced directly in the select list as well as by reference in the HAVING clause. So it gets correctly fixed even with prepared statements. And since the Item_null_helper subclass of Item_ref_null_helper is not used anywhere else it's taken out. |
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| .. | ||
| include | ||
| lib | ||
| misc | ||
| ndb | ||
| r | ||
| std_data | ||
| suite/jp | ||
| 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.pl | ||
| mysql-test-run.sh | ||
| mysql_test_run_new.c | ||
| README | ||
| README.gcov | ||
| resolve-stack | ||
| suppress.purify | ||
This directory contains a test suite for the 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. 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 for instructions on how to report the problem: http://dev.mysql.com/doc/mysql/en/mysql-test-suite.html If you want to use an already running MySQL server for specific tests, use the --extern option to mysql-test-run. Please note that in this mode, the test suite expects you to provide the names of the tests to run. For example, here is the command to run the "alias" and "analyze" tests with an external server: mysql-test-run --extern alias analyze To match your setup, you might also need to provide --socket, --user, and other relevant options. With no test cases named on the command line, mysql-test-run falls back to the normal "non-extern" behavior. The reason for this is that some tests cannot run with an external server. You can create your own test cases. To create a test case, create a new file in the t subdirectory using a text editor. The file should have a .test extension. For example: xemacs t/test_case_name.test In the file, put a set of SQL statements that create some tables, load test data, and run some queries to manipulate it. We would appreciate it if you name your test tables 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 ensures that you can run the test over and over again. If you are using mysqltest commands (like result file names) in your test case, you should 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 consisting of SQL statements and comments, you can create the test case in 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 incorrect, 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