Good day, I use pgsql 7.4: I would like to know if indexes will solve my problem (I fear the system will become slow with the time). And also some questions on how pgsql optimise for speed.
*Database* -- Assuming those tables (not original, but enought to get the point): CREATE TABLE prod.jobs ( job_id serial PRIMARY KEY, order_id integer NOT NULL REFERENCES sales.orders, ); CREATE TABLE design.products ( product_id serial PRIMARY KEY, company_id integer NOT NULL REFERENCES sales.companies ON UPDATE CASCADE, product_code varchar(24) NOT NULL, CONSTRAINT product_code_already_used_for_this_company UNIQUE (company_id, product_code) ); CREATE TABLE prod.jobs_products ( product_id integer REFERENCES design.products ON UPDATE CASCADE, ) INHERITS (prod.jobs); -- Assuming this view: CREATE VIEW prod.orders_jobs_view AS SELECT job_id, order_id, product_code FROM ( SELECT *, NULL AS product_id FROM ONLY prod.jobs UNION SELECT * FROM prod.jobs_products ) AS alljobs LEFT JOIN design.products ON alljobs.product_id = products.product_id; *Question 1* Assuming this request: SELECT * FROM prod.orders_jobs_view WHERE order_id = 1; I imagine that somewhere down the road, this will get slow since there is no index on the order_id. I tought of creating two indexes... With the previous VIEW and database schema, will the following boost the DB; as I don't know how PostgreSQL works internally: CREATE UNIQUE INDEX order_jobs ON prod.jobs(order_id); CREATE UNIQUE INDEX order_jobs_products ON prod.jobs_products(order_id); *Question 2* If no to question 1, what can I do to boost the database speed. I do have prety heavy views on data, and I would like to get some speed as the DB will get filled up quickly. *Question 3* When creating a wien with linked "UNION" tables as previous... when we do a SELECT with a WHERE clause, will the database act efficiently by adding the WHERE clause to the UNIONed tables in the FROM clause? Example: SELECT * FROM prod.orders_jobs_view WHERE order_id = 1; whould cause something like SELECT job_id, order_id, product_code FROM ( SELECT *, NULL AS product_id FROM ONLY prod.jobs WHERE order_id = 1 UNION SELECT * FROM prod.jobs_products WHERE order_id = 1 ) AS alljobs LEFT JOIN design.products ON alljobs.product_id = products.product_id; in order to speed the union processing? Thank you for any help on this. -- Alexandre Leclerc ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html