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![]() This patch implements basic IDENTITY feature, with the following syntax: <col> GENERATED {ALWAYS AS | BY DEFAULT [ON NULL]} identity_props The following identity_props are recognized and saved in the table metadata, but ignored - START WITH num - INCREMENT BY num - MAXVALUE num - MINVALUE num - ORDER, NOORDER - CYCLE, NOCYCLE - NOMINVALUE, NO MINVALUE - NOMAXVALUE, NO MAXVALUE The following identity_props are newly added keywords, however they are not reserved, i.e. can be used as identifiers, column names, etc. just as before: - KEEP - SCALE - SHARD - EXTEND - NOKEEP - NOSCALE - NOSHARD - NOEXTEND The patch is designed in minimalistic manner, re-using existing AUTO_INCREMENT implementation, yet utilizing the default values evaluation mechanism. As a result, it grants usage of CHECK constraints and other table expressions: vcols, default values with identity column. Some notes: * IDENTITY is evaluated as Field's default_value. Even GENERATED ALWAYS is considered "default", since the IDENTITY expression is not determistic. * However, the GENERATED ALWAYS kind cannot be assigned in DMLs in STRICT SQL_MODE. That is, the behavior for users is like for other GENERATED ALWAYS columns. * It honors INSERT_ID and uses it, which is important for statement-based replication to work. * START WITH and INCREMENT BY are ignored. auto_increment_increment and auto_increment_offset are being followed instead, exactly as for AUTO_INCREMENT. * Since IDENTITY behaves as DEFAULT, it cannot follow NO_AUTO_VALUE_ON_ZERO and should accept user-set keyword with zeroes, even when it is off, otherwise, `default` will not work. See test "Zeroes and defaults handling". * IDENTITY column is always replicated and saved in mariadb-dump, which is guaranteed by using default_value instead of vcol_expr (vcols, even stored, are usually not replicated). * In frm, it is loaded and saved as a default expression. For that, parse_vcol_expr definition was extended to support things like GENERATED BY DEFAULT, and even GENERATED ALWAYS. That is, no EXTRA2 header had to be added. * AUTO_INCREMENT is not transformed into default_value and works completely as before. * IDENTITY should work without the key, and moreover should generate new values without repetition. If no suitable key is created by user, one is created implicitly. * New IDENTITY keyword is added as not-reserved. handler::update_auto_increment: extract a part checking for explicit value and zeroes. Invoke only for AUTO_INCREMENT. The rest is contained in handler::update_auto_increment_impl, which will be invoked by IDENTITY. Add field argument to use instead of next_number_field. Note that for IDENTITY, field is not always next_number_field (Item_default_value can create its own field). * show_create.cc: changes make it possible to output Field's default_value as GENERATED BY DEFAULT, instead of DEFAULT (expr). * Item_field::check_vcol_func_processor: allow default on IDENTITY fields (they still have AUTO_INCREMENT properties, like unireg_check) * Item_default_value::tie_field: forbid default(x) exprs. Item_default_value distinguishes `default` and `default(x)` by the vcol_assignment_ok flag. * mysql_prepare_create_table_finalize: make sure there is at least one key where IDENTITY field goes as a first key_part. If there's none - create one. Known issues: * LAST_INSERT_ID() is not working for now. Limitations: * default(identity_column), is disabled, because persistent write is not properly done in that case. |
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.. | ||
collections | ||
include | ||
lib | ||
main | ||
std_data | ||
suite | ||
asan.supp | ||
CMakeLists.txt | ||
dgcov.pl | ||
lsan.supp | ||
mariadb-stress-test.pl | ||
mariadb-test-run.pl | ||
mtr.out-of-source | ||
purify.supp | ||
README | ||
README-gcov | ||
README.stress | ||
suite.pm | ||
valgrind.supp |
This directory contains test suites for the MariaDB server. To run currently existing test cases, execute ./mysql-test-run in this directory. Some tests are known to fail on some platforms or be otherwise unreliable. In the file collections/smoke_test there is a list of tests that are expected to be stable. In general you do not have to do "make install", and you can have a co-existing MariaDB installation, the tests will not conflict with it. To run the tests in a source directory, you must do "make" first. In Red Hat distributions, you should run the script as user "mysql". The user is created with nologin shell, so the best bet is something like # su - # cd /usr/share/mariadb-test # su -s /bin/bash mysql -c ./mysql-test-run This will use the installed MariaDB executables, but will run a private copy of the server process (using data files within /usr/share/mariadb-test), so you need not start the mysqld service beforehand. You can omit --skip-test-list option if you want to check whether the listed failures occur for you. To clean up afterwards, remove the created "var" subdirectory, e.g. # su -s /bin/bash - mysql -c "rm -rf /usr/share/mariadb-test/var" If tests fail on your system, please read the following manual section for instructions on how to report the problem: https://mariadb.com/kb/en/reporting-bugs 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, you are expected to provide names of the tests to run. For example, here is the command to run the "alias" and "analyze" tests with an external server: # mariadb-test-run --extern socket=/tmp/mysql.sock alias analyze To match your setup, you might need to provide other relevant options. With no test names on the command line, mysql-test-run will attempt to execute the default set of tests, which will certainly fail, because many tests cannot run with an external server (they need to control the options with which the server is started, restart the server during execution, etc.) You can create your own test cases. To create a test case, create a new file in the main 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. 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 in your test case, you should create the result file as follows: # mariadb-test-run --record test_case_name or # mariadb-test --record < t/test_case_name.test If you only have a simple test case consisting of SQL statements and comments, you can create the result file in one of the following ways: # mariadb-test-run --record test_case_name # mariadb test < t/test_case_name.test > r/test_case_name.result # mariadb-test --record --database test --result-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. If you want to submit your test case you can send it to developers@lists.mariadb.org or attach it to a bug report on http://mariadb.org/jira/. If the test case is really big or if it contains 'not public' data, then 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://ftp.mariadb.org/private and submit a report to https://mariadb.org/jira about it. The latest information about mysql-test-run can be found at: https://mariadb.com/kb/en/mariadb/mysqltest/ If you want to create .rdiff files, check https://mariadb.com/kb/en/mariadb/mysql-test-auxiliary-files/