#MARIADB VARCHAR LENGTH UPDATE#
#MARIADB VARCHAR LENGTH CODE#

Each TEXT value is stored using a two-byte length prefix that indicates the number of bytes in the value. The effective maximum length is less if the value contains multi-byte characters. E.G to instruct the developer to check the documentation and for the limits based on the character set they are using for the database/table/column.Syntax TEXT DescriptionĪ TEXT column with a maximum length of 65,535 ( 2 16 - 1) characters.

#MARIADB VARCHAR LENGTH UPDATE#

Change checks.Error on line 40 to checks.Warning and update the error message to be one that is more useful.Remove lines 37 through 45 of db._field_type as they are simply not needed as the DB itself will trigger an error.I would just make the change and publish a PR for it myself but I'm unsure on how best to write the unit tests without them being actual integration tests other than using mocks to raise the error or not but then it seems rather pointless of a test. That would be great from my point of view. I'm new to this codebase, so I might need a little help if that's okay :) Hi! I would like to take up this issue if no one is already working on it. So the Error Code: 1071 will trigger again Then simple try to index one more character and you will be over the byte lengthĪLTER TABLE `example3`.`example` ADD UNIQUE INDEX `test_unique2` (`column1`(769)) Here is an example of the maximum UTF8MB4 index being createdĪLTER TABLE `example3`.`example` ADD UNIQUE INDEX `test_unique2` (`column1`(768)) This will again generate the an Error Code: 1071 - Specified key was too long max key length is 3072 bytes Here is a 3rd example showing an UTF8MB4 tableĬREATE DATABASE `example3`CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci ĬREATE TABLE `example3`.`example` ( `column1` VARCHAR(3072) ) ENGINE=INNODB CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci ĪLTER TABLE `example3`.`example` ADD UNIQUE INDEX `test_unique` (`column1`(3072)) Specified key was too long max key length is 3072 bytes Here is an example of one where the Error Code: 1071 will be triggeredĬREATE DATABASE djangotest2 CHARACTER SET utf8 COLLATE utf8_general_ci įor this you will receive the following error: Here is an example of creating indexes on a UTF-8 table that will not errorĬREATE DATABASE djangotest CHARACTER SET utf8 COLLATE utf8_general_ci

#MARIADB VARCHAR LENGTH CODE#

So users will not be aware that DB doesn't protect uniqueness.Īs a longtime certificate MySQL Dev I can assure you that both MySQL and MariaDB both do not act in this way and will raise error code 1071 (E.G 'Specified key was too long max key length is 3072 bytes') if you try to create an index that is too large. 191 characters and ignores the remaining chars. I'm not a MySQL expert, but I think that MySQL doesn't raise any error it'll just create an unique constraint for the first e.g.

It just needs the max length to be increased on line 38 of db. It's only CHAR that is restricted to 255 and as Django creates VARVCHARs there is no need to enforce that limit.ĬREATE DATABASE testCHARACTER SET utf8 COLLATE utf8_general_ci MySQL supports VARCHARs of up to 65,535 length. There is a bug within db._field_type where the maximum unique constraints is still being limited to 255 characters even though MySQL supports unique keys of up to 1000 characters by default and InnoDB supports 3072 bytes for InnoDB tables that use DYNAMIC or COMPRESSED row format and 767 bytes for InnoDB tables that use the REDUNDANT or COMPACT row format.

Mariadb varchar length