Hi Jared. I read your pg link in detail a couple of times and this could be interesting for MySQL users,especially those implementing large time-series databases and some multi-tenant scenarios. Can you write up the jira as requested and I'll comment more there? (Note that example 11.3 can be accomplished in both pg and MySQL usingNULLs in a unique index, but the pg partial index allows the original data valuesto be used without a NULL work column, so might be slightly more convenient/obvious.)  Thanks, James Briggs. -- Cassandra/MySQL DBA. Available in San Jose area or remote. cass_top: https://github.com/jamesbriggs/cassandra-top From: Sergei Golubchik To: Jared Beck Cc: maria-developers@lists.launchpad.net Sent: Wednesday, December 27, 2017 12:30 PM Subject: Re: [Maria-developers] Partial indexes? Hi, Jared! On Dec 27, Jared Beck wrote:

Dear Maria,

:p

Thanks for all your hard work!

Any plans to implement partial indexes? (https://www.postgresql.org/docs/10/static/indexes-partial.html)

No such plans at the moment. What do you you need them for?

I hope this is the right place to suggest new features. Please redirect me if not.

To suggest a new feature, you can create a task at jira.mariadb.org (presuming such a task doesn't exist yet). But a mailing list is a better place if you want to start a discussion. If, for example, you'd like to show valid use cases for partial indexes or explain why it's an important feature to have :) Regards, Sergei Chief Architect MariaDB and security@mariadb.org _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to    : maria-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-developers More help  : https://help.launchpad.net/ListHelp

Yes, that's another good example of 11.3 where you caneither use a pg partial index, or a pg/mysql unique nullable column with active=true or null.  Thanks, James Briggs. -- Cassandra/MySQL DBA. Available in San Jose area or remote. cass_top: https://github.com/jamesbriggs/cassandra-top From: Jared Beck To: Sergei Golubchik Cc: maria-developers@lists.launchpad.net Sent: Wednesday, December 27, 2017 4:52 PM Subject: Re: [Maria-developers] Partial indexes? On Wed, Dec 27, 2017 at 3:30 PM, Sergei Golubchik wrote:

...

Any plans to implement partial indexes? (https://www.postgresql.org/docs/10/static/indexes-partial.html)

No such plans at the moment. What do you you need them for?

I have used unique partial indexes to enforce business rules like "Active users must have a unique phone number, but there may be any number of inactive users with the same phone number" ``` create unique index ix_active_phones on users (phone) where active = true ; ``` -- Jared Beck • (607) 216-5373 • jared@jaredbeck.com _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to    : maria-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-developers More help  : https://help.launchpad.net/ListHelp

On Thu, Dec 28, 2017 at 9:34 AM, Sergei Golubchik wrote:

In MariaDB (and in SQL standard) the way to achieve that would be to use a nullable column for active, and mark inactive users with NULL. Then you can create a unique index on (phone,active).

That is a neat trick, thanks James and Sergei! -- Jared Beck • (607) 216-5373 • jared@jaredbeck.com