Re: [GENERAL] Transactional vs. Read-only (Retrieval) database

Le Jeudi 11 Avril 2002 15:14, Samuel J. Sutjiono a écrit :
> I'd like to get some opinions if there are any benefits (i.e. in terms of
> performance) of creating two separate databases, one for transactions
> (insert, update, delete) and the other one is for retrieval/search
> (select).

Dear Samuel,

You do not need to create two separate databases. It is possible to write 
server-side code to copy static data (read-only) to other tables. This can be 
done using triggers and/or cron jobs.

A more sopisticated solution would be to store LEFT JOIN query results in the 
original table using triggers. For example : you have tables COMPANY and 
EMPLOYEE. Instead of running a LEFT JOIN on EMPLOYEE->COMPANY, it is possible 
to store COMPANY name in table employee using a trigger.

Then, you don't need LEFT JOINS any more, simple SELECTs are enough, which is 
fantastic for heavy loaded databases.

Same as for many operations. Try the EXPLAIN clause on a query. If too heavy, 
try to write some code to simplify the query using triggers...

PostgreSQL is the most advanced open-source database available today. It has 
several server-side languages (plpgsql, plperl, plpython). Maybe you should 
try plpgsql which is easy to learn.

Well-optimized, PostgreSQL can run 10 times faster than well-known open-source 
databases. If you need to test server-side programming, do not hesitate to 
download and install pgAdmin2 (http://pgadmin.postgresql.org), PostgreSQL 
Windows GUI.

Cheers,
Jean-Michel