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DATE and DATETIME can be compared either as strings or as int. Both methods have their disadvantages. Strings can contain valid DATETIME value but have insignificant zeros omitted thus became non-comparable with other DATETIME strings. The comparison as int usually will require conversion from the string representation and the automatic conversion in most cases is carried out in a wrong way thus producing wrong comparison result. Another problem occurs when one tries to compare DATE field with a DATETIME constant. The constant is converted to DATE losing its precision i.e. losing time part. This fix addresses the problems described above by adding a special DATE/DATETIME comparator. The comparator correctly converts DATE/DATETIME string values to int when it's necessary, adds zero time part (00:00:00) to DATE values to compare them correctly to DATETIME values. Due to correct conversion malformed DATETIME string values are correctly compared to other DATE/DATETIME values. As of this patch a DATE value equals to DATETIME value with zero time part. For example '2001-01-01' equals to '2001-01-01 00:00:00'. The compare_datetime() function is added to the Arg_comparator class. It implements the correct comparator for DATE/DATETIME values. Two supplementary functions called get_date_from_str() and get_datetime_value() are added. The first one extracts DATE/DATETIME value from a string and the second one retrieves the correct DATE/DATETIME value from an item. The new Arg_comparator::can_compare_as_dates() function is added and used to check whether two given items can be compared by the compare_datetime() comparator. Two caching variables were added to the Arg_comparator class to speedup the DATE/DATETIME comparison. One more store() method was added to the Item_cache_int class to cache int values. The new is_datetime() function was added to the Item class. It indicates whether the item returns a DATE/DATETIME value.
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