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Migrating 1200 databases from MySQL to Postgres

psyenix.blogspot.com

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Re: Migrating 1200 databases from MySQL to Postgres

#81

Post by fulafel »

berns wrote: post #77
fulafel wrote: post #69

Earlier quoted context omitted.

My misunderstanding seemed to be that "accent-insensitive" turns out to be a precise technical term from MySQL that says "just sort UTF-8 using the American locale and collation, but pretend accented characters are equal to their non-accented versions" which is not a standard collation order in any locale.

I think this is incorrect. In Mysql utf8_spanish_ci and utf8_swedish_ci have different accent rules, for example.

But then what would be the case for using accent-ignoring spanish collation rules, rather than the default spanish collation rules that sort accented chars according to normal spanish sorting? This sounds strictly inferior in any human facing application.

Re: Migrating 1200 databases from MySQL to Postgres

#82

Post by branko_d »

kondro wrote: post #65
gaius wrote: post #57

Earlier quoted context omitted.

Was this a big deal in the past? In MySQL, yes. It lacked the concept of foreign keys.

Lack of foreign keys does not effect performance. In fact, having foreign keys is a net-negative performance-wise because it means that each foreign key must be checked for every insert/update/delete.

Foreign keys can improve performance, in some cases:

https://stackoverflow.com/a/8154375/533120

Re: Migrating 1200 databases from MySQL to Postgres

#84

Post by bmn__ »

berns wrote: post #18

One thing that Postgres lacks is accent insensitive collations. Having clients with databases in Spanish, this is one of the reasons I wouldn't consider migrating to Postgres. I know I can use the unaccent extension, but I consider it a poor substitute to proper collations. I guess this isn't a problem for most people because it's never mentioned.

> One thing that Postgres lacks is accent insensitive collations.

So what if the functionality is not in core, but in an extension? You make it sound as if it does not exist at all and all we can do is gnash our teeth in frustration.

http://www.public-software-group.org/pg_collkey

first release in 2006 for PostgreSQL 8

Re: Migrating 1200 databases from MySQL to Postgres

#85

Post by karmakaze »

berns wrote: post #18

One thing that Postgres lacks is accent insensitive collations. Having clients with databases in Spanish, this is one of the reasons I wouldn't consider migrating to Postgres. I know I can use the unaccent extension, but I consider it a poor substitute to proper collations. I guess this isn't a problem for most people because it's never mentioned.

Why not just use a functional index? I'd expect it to have much better performance.
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