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that implement add_index The problem was that ALTER TABLE blocked reads on an InnoDB table while adding a secondary index, even if this was not needed. It is only needed for the final step where the .frm file is updated. The reason queries were blocked, was that ALTER TABLE upgraded the metadata lock from MDL_SHARED_NO_WRITE (which blocks writes) to MDL_EXCLUSIVE (which blocks all accesses) before index creation. The way the server handles index creation, is that storage engines publish their capabilities to the server and the server determines which of the following three ways this can be handled: 1) build a new version of the table; 2) change the existing table but with exclusive metadata lock; 3) change the existing table but without metadata lock upgrade. For InnoDB and secondary index creation, option 3) should have been selected. However this failed for two reasons. First, InnoDB did not publish this capability properly. Second, the ALTER TABLE code failed to made proper use of the information supplied by the storage engine. A variable need_lock_for_indexes was set accordingly, but was not later used. This patch fixes this problem by only doing metadata lock upgrade before index creation/deletion if this variable has been set. This patch also changes some of the related terminology used in the code. Specifically the use of "fast" and "online" with respect to ALTER TABLE. "Fast" was used to indicate that an ALTER TABLE operation could be done without involving a temporary table. "Fast" has been renamed "in-place" to more accurately describe the behavior. "Online" meant that the operation could be done without taking a table lock. However, in the current implementation writes are always prohibited during ALTER TABLE and an exclusive metadata lock is held while updating the .frm, so ALTER TABLE is not completely online. This patch replaces "online" with "in-place", with additional comments indicating if concurrent reads are allowed during index creation/deletion or not. An important part of this update of terminology is renaming of the handler flags used by handlers to indicate if index creation/deletion can be done in-place and if concurrent reads are allowed. For example, the HA_ONLINE_ADD_INDEX_NO_WRITES flag has been renamed to HA_INPLACE_ADD_INDEX_NO_READ_WRITE, while HA_ONLINE_ADD_INDEX is now HA_INPLACE_ADD_INDEX_NO_WRITE. Note that this is a rename to clarify current behavior, the flag values have not changed and no flags have been removed or added. Test case added to innodb_mysql_sync.test. |
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| suite | ||
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| CMakeLists.txt | ||
| mtr.out-of-source | ||
| mysql-stress-test.pl | ||
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| README | ||
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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