If everything went well, at the end you should have output similar to: +-+-+ If you want to generate random password, you can make use of this function which generate random number. VALUES (uuid_to_bin(uuid()), 'Larry Page') In MySQL, UUID() function returns Universal Unique Identifier that generates 36 characters long value which is 5 part hexadecimal numbers. Here's an example where a table users uses binary UUIDs for its primary key: CREATE TABLE users CREATE TRIGGER beforeinsertmytable BEFORE INSERT ON mytable FOR EACH ROW SET new.LogID uuid () The UUID () expression generates a UUID when called. , 9, 0, '-'), 14, 0, '-'), 19, 0, '-'), 24, 0, '-') Just create a trigger to run before insert to generate the UUID for the given column. MySQL v8.0.0 (2016) added the function UUID_TO_BIN() which does the same thing: SELECT uuid_to_bin("f7c26694-aac6-4333-91c9-72c4441430e2") AS uuid_bin +-+Īnd it's easy to perform the reverse here: SELECT lower( insert( insert( insert( insert( It seems when surrounding the subquery to generate a UUID with REPLACE, it only runs the UUID. Even better, comparison and sorting will use the numeric value of the column, which will perform much better than a string.Īll versions of MySQL can use UNHEX() and REPLACE() to do this: SELECT UNHEX(REPLACE("f7c26694-aac6-4333-91c9-72c4441430e2", "-", "")) AS unhex_replace +-+ Im using MySQL Server version: 5.5.40-0+wheezy1 (Debian). I prefer UUID v4 because of its physical machine independence. I already have systems that use MySQL, and I would prefer to stay with the same DBMS. MySQLs UUID () function generates v1 UUIDs, which have a time component that make them unevenly distributed over short periods of time. They will generate their own UUID, then insert it later (offline insert). The BINARY type isn't affected by the table character set (such as utf8mb4), it uses the binary character set and collation. Many systems will insert to the table, some may specify a UUID when inserting, but some will not. If we strip the hyphens and convert the remaining 32 characters to BINARY, we can store UUIDs in only 16 bytes. UUIDs are supposed to be only 16 bytes, can't we do better? Binary UUID columns Universally unique identifiers (UUIDs) are 128-bit (16-byte) numbers that are designed to be globally unique, and as a result they make for great primary keys. Why You Should Use UUIDs for Your Primary Keys
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