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CAUSES RESTORE PROBLEM Problem Statement: ------------------ mysqldump is not having the dump stmts for general_log and slow_log tables. That is because of the fix for Bug#26121. Hence, after dropping the mysql database, and applying the dump by enabling the logging, "'general_log' table not found" errors are logged into the server log file. Analysis: --------- As part of the fix for Bug#26121, we skipped the dumping of tables for general_log and slow_log, because the data dump of those tables are taking LOCKS, which is not allowed for log tables. Fix: ---- We came up with an approach that instead of taking both meta data and data dump information for those tables, take only the meta data dump which doesn't need LOCKS. As part of fixing the issue we came up with below algorithm. Design before fix: 1) mysql database is having tables like db, event,... general_log, ... slow_log... 2) Skip general_log and slow_log while preparing the tables list 3) Take the TL_READ lock on tables which are present in the table list and do 'show create table'. 4) Release the lock. Design with the fix: 1) mysql database is having tables like db, event,... general_log, ... slow_log... 2) Skip general_log and slow_log while preparing the tables list 3) Explicitly call the 'show create table' for general_log and slow_log 3) Take the TL_READ lock on tables which are present in the table list and do 'show create table'. 4) Release the lock. While taking the meta data dump for general_log and slow_log the "CREATE TABLE" is replaced with "CREATE TABLE IF NOT EXISTS". This is because we skipped "DROP TABLE" for those tables, "DROP TABLE" fails for these tables if logging is enabled. Customer is applying the dump by enabling logging so, if the dump has "DROP TABLE" it will fail. Hence, removed the "DROP TABLE" stmts for those tables. After the fix we could observe "Table 'mysql.general_log' doesn't exist" errors initially that is because in the customer scenario they are dropping the mysql database by enabling the logging, Hence, those errors are expected. Once we apply the dump which is taken before the "drop database mysql", the errors will not be there. client/mysqldump.c: In get_table_structure() added code to skip the DROP TABLE stmts for general_log and slow_log tables, because when logging is enabled those stmts will fail. And replaced CREATE TABLE with CREATE IF NOT EXISTS for those tables, just to make sure CREATE stmt for those tables doesn't fail since we removed DROP stmts for those tables. In dump_all_tables_in_db() added code to call get_table_structure() for general_log and slow_log tables. mysql-test/r/mysqldump.result: Added a test as part of fix for Bug #11754178 mysql-test/t/mysqldump.test: Added a test as part of fix for Bug #11754178 |
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| Makefile.am | ||
| 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