The following bug has been logged online:

Bug reference: 1283
Logged by: Fabio Fucci

Email address: ffucci (AT) kell (DOT) it

PostgreSQL version: 7.3

Operating system: linux

Description: Queries slow down after restoring big db

Details:

We dumped a database with a lot of data using command pg_dump mydb >
mydb.dump

Then we reimported the data in this way:
1- createdb anotherdb
2- psql anotherdb < mydb.dump

After the data was restored queries(SELECT queries, with JOINs) was very
very slow.

We solved the problem making a separate dump for the database schema and one
for the data and then reimported first the schema and then the data.


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TIP 9: the planner will ignore your desire to choose an index scan if your
joining column's datatypes do not match

"PostgreSQL Bugs List" <pgsql-bugs (AT) postgresql (DOT) org> writes:
Did you ANALYZE after importing?

regards, tom lane

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