[Maria-discuss] innodb table single column index max length
we know the mysql have a limit that the max index length on a single column is 767.I want know how the 767 come from ? why not 799 or 800 etc.
Hi, butler! On Apr 17, butler wrote:
we know the mysql have a limit that the max index length on a single column is 767.I want know how the 767 come from ? why not 799 or 800 etc.
768 is 256*3, originally selected to fit 256 characters in utf8 charset, each character can be up to 3 bytes long. 767 is 768-1. Regards, Sergei Chief Architect MariaDB and security@mariadb.org
I just want to know ,Why need fit 256 characters in utf8 charset。Why not 512 characters in utf8 charset ? ------------------ Original ------------------ From: "Sergei Golubchik";<serg@mariadb.org>; Date: Tue, Apr 18, 2017 03:14 AM To: "butler"<zxszcaijin@qq.com>; Cc: "maria-discuss"<maria-discuss@lists.launchpad.net>; Subject: Re: [Maria-discuss] innodb table single column index max length Hi, butler! On Apr 17, butler wrote:
we know the mysql have a limit that the max index length on a single column is 767.I want know how the 767 come from ? why not 799 or 800 etc.
768 is 256*3, originally selected to fit 256 characters in utf8 charset, each character can be up to 3 bytes long. 767 is 768-1. Regards, Sergei Chief Architect MariaDB and security@mariadb.org
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butler -
Sergei Golubchik