[GENERAL] pg_trgm extension and theory

Hello to all experts, I am considering of using pg_trgm extension in a research publication, since initial results seem promising. The index seems to works pretty fast for finding similar text and significantly accelerate query time. The problem is that I do not know the theory behind it or the ex

[GENERAL] union of types in a different category

According to clause 3 on http://www.postgresql.org/docs/9.3/static/typeconv-union-case.html regarding union type matching: 3. If the non-unknown inputs are not all of the same type category, fail. So a query "SELECT 1 UNION SELECT 1.1" works because 1 and 1.1 are of the same category, and one

Re: [GENERAL] union of types in a different category

> > Interestingly - & i'm curious as to why" > > SELECT '1' UNION SELECT 2; > ?column? > -- > 1 > 2 > (2 rows) > > SELECT '1' UNION SELECT 1; > ?column? > -- > 1 > (1 row) > > > I didn't think UNION did an explicit "distinct" - if that is what is > ha

Re: [GENERAL] union of types in a different category

> > I prefer the explicit approach used by Postgres - MYSQL is simpler, but I'd > say > simplistic in this area. While it can automate the cating of tpes/catories of > variable, it doesn't always do it the way I want - so I need to be explicit > anyway. > > In your second use case, which fails -

[GENERAL] Database creation: default permissions, owner of cloned elements

Hey all, I'm a bit confused about the way databases are created in postgresql, and the permissions that are set for new databases. First of all I was surprised, that the default database template (template1) has privileges for the public schema by default. That seems a bit too permissive to me, h

Re: [GENERAL] union of types in a different category

I prefer the explicit approach used by Postgres - MYSQL is simpler, but I'd say simplistic in this area. While it can automate the cating of tpes/catories of variable, it doesn't always do it the way I want - so I need to be explicit anyway. In your second use case, which fails - do you want nu

Re: [GENERAL] union of types in a different category

James Harper writes: > According to clause 3 on > http://www.postgresql.org/docs/9.3/static/typeconv-union-case.html regarding > union type matching: > 3. If the non-unknown inputs are not all of the same type category, fail. > So a query "SELECT 1 UNION SELECT 1.1" works because 1 and 1.1 are

Re: [GENERAL] union of types in a different category

> Did you try it? > > postgres=# SELECT '1' UNION SELECT 2; > ?column? > -- > 1 > 2 > (2 rows) > > Now, if I'd done this it would fail: > > postgres=# SELECT '1'::text UNION SELECT 2; > ERROR: UNION types text and integer cannot be matched > LINE 1: SELECT '1'::text UNI

[GENERAL] stand by is starting until I do some work in the primary

Today I reinstall a pg extension,then restart the primary and slave. the primary is OK and I can login,and the pg_stat_replication view show the slave is connected. but when I try to login the slave,it shows: FATAL:the database system is starting up I wait several minutes,but it still show the sam

Re: [GENERAL] stand by is starting until I do some work in the primary

On Sun, Feb 23, 2014 at 12:18 PM, Jov wrote: > Today I reinstall a pg extension,then restart the primary and slave. the > primary is OK and I can login,and the pg_stat_replication view show the > slave is connected. > but when I try to login the slave,it shows: > FATAL:the database system is star

Re: [GENERAL] stand by is starting until I do some work in the primary

Sure.Before the restart,I have login in the slave many times. some more info ,but I don't think related: centOS 6 ,amd64,128GB memory,24 core, pgsql-9.3.3,master and slave in the same host. this is my first instance of 9.3，I don't exprence this before on 9.0~9.2. Jov blog: http:amutu.com/blog