Am 30.01.2014 19:36, schrieb Roberto Spadim:
nice, now one question... what about views? how many columns? what about spider engine with vertical partition? how many columns?
views - caution - no materialized views in MySQL means implicit querys in the background while you tink your select statement is tiny and fast :-) http://en.wikipedia.org/wiki/Materialized_view in general i would say avoid too many columns and consider what is really accessed always at the same time and what can be in a different table with a foreign key / reference
2014-01-30 Reindl Harald <h.reindl@thelounge.net>:
http://dev.mysql.com/doc/refman/5.5/en/column-count-limit.html
normally you have a serious problem if you reach that limits because it won't scale well and the scheme is at least questionable
select(*) even with most empty will create large results inserts/updates are much slower
Am 30.01.2014 18:50, schrieb Roberto Spadim:
hum, unireg is the "global" limit, there's some ideas to change the .frm file and create a better one with less limits (drizzle database have it done), but you have limits in each engine too, index size have limits, many limits per engine exists, i think a max columns is just more one
how many columns you need? i think it's the best question, after that select a engine, if it's not a good engine, create many tables and use spider engine to group all tables (vertical partition) ?
2014-01-30 Adam Scott <adam.c.scott@gmail.com <mailto:adam.c.scott@gmail.com>>:
I believe it's the same as in MySQL. It does depend on the engine your table is using. By default it is probably InnoDB.
For the full details about the limits: http://www.mysqlperformanceblog.com/2013/04/08/understanding-the-maximum-num...
On Thu, Jan 30, 2014 at 9:45 AM, AskMonty KB <noreply@askmonty.org <mailto:noreply@askmonty.org>> wrote:
Hello,
A new question has been asked in "MariaDB FAQ" by robpaton: -------------------------------- Hi there,
What is the maximum number of columns a row can have in MariaDB? I can't find this info anywhere on the web.
Best regards, Rob --------------------------------