Thread: Emergency questions for new bie

Emergency questions for new bie

From
Jack Zhu
Date:
Hi,

I'm an Oracle DBA, lately I  began a project work on  PostgreSQL 6.5.3
for Red Hat Linux 6.0.

Every thing is fine, except:

1.How can I enable PG run as 'no-fsync' mode to improve performance? How
can I check PG is in 'fsync' mode or not?

2. We have a table contain a column which use 'timestamp' data type.
'cause we need both date and time in this column, and don't want to
break it into two columns with 'date' and 'time' data type(if so, we may
have to change thousands of lines code, it origrinally works on Oracle).
But when I tried to create an index on this 'timestamp' column, I got
this error and creating failed: 'Cannot find a default operator class
for type 1296.'

I use this SQL command to create index: create index ind_name on
tab_name(col_name);

Can't I create index on 'timestamp' column? Right now since there's no
index on this column, our app runs very very slow!

THanks a lot!

Jack


Re: Emergency questions for new bie

From
Peter Eisentraut
Date:
Jack Zhu writes:

> 1.How can I enable PG run as 'no-fsync' mode to improve performance?

postmaster -o '-F'

> How can I check PG is in 'fsync' mode or not?

It is if and only if you give the above option.

> But when I tried to create an index on this 'timestamp' column, I got
> this error and creating failed: 'Cannot find a default operator class
> for type 1296.'

Indexes don't work for timestamp in 6.5. Use datetime, or better yet
upgrade to 7.0 which should be out in a few weeks. (jinx)


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