If you can write an expression which returns the JSON attribute, yes, the (trivial) technique I described in the post can do that. I think that MySQL 5.7 JSON functions are not yet in MariaDB. But maybe they can be added easily? Or again, maybe you can use MariaDB 10 regexp's?

Federico

-------------------------------------------- El sáb, 26/4/14, MARK CALLAGHAN mdcallag@gmail.com escribió:

Asunto: [Maria-discuss] virtual columns and indexes on attributes in JSON objects Para: "Maria Discuss" maria-discuss@lists.launchpad.net Fecha: sábado, 26 de abril, 2014 17:29

Does the support for virtual columns allow an index to be created on an attribute in a JSON object stored in a BLOB column?

http://falseisnotnull.wordpress.com/2014/04/25/descending-indexes-in-mariadb

https://mariadb.com/kb/en/virtual-columns/

-- Mark Callaghan mdcallag@gmail.com

-----Adjunto en línea a continuación-----

_______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to     : maria-discuss@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-discuss More help   : https://help.launchpad.net/ListHelp

Sure, you can do that. You do it by creating a persistent virtual column on the attribute, using COLUMN_GET probably, and then creating a column on that. In a presentation on JSON and MySQL / MariaDB I show a simple example of this: http://www.slideshare.net/blueskarlsson/using-json-with-mariadb-and-mysql See slide 20

Of course we would like this to be even smarter, but this is what is available and works as we speak.

/Karlsson MARK CALLAGHAN skrev 2014-04-26 17:29:

Does the support for virtual columns allow an index to be created on an attribute in a JSON object stored in a BLOB column?

http://falseisnotnull.wordpress.com/2014/04/25/descending-indexes-in-mariadb https://mariadb.com/kb/en/virtual-columns/

-- Mark Callaghan mdcallag@gmail.com mailto:mdcallag@gmail.com

_______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to : maria-discuss@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-discuss More help : https://help.launchpad.net/ListHelp