Learning PostgreSQL

PostgreSQL benchmarks

An important question regarding a database system is: how fast is it? How many transactions can it handle per second, or how much time a particular query takes to execute? The topic on the performance of a database has been covered in Chapter 10, Optimizing Database Performance. Here, we will only discuss the task of measuring it.

The Psql meta-command \timing is used to measure the time of execution of a particular SQL command. Once timing is enabled, psql shows the time of execution for each command:

car_portal-# \timing
Timing is on.
car_portal=# SELECT count(*) FROM car_portal_app.car;
 count
-------
   229
(1 row)
Time: 19.492 ms

Usually, that is enough to understand which query is faster. However, one cannot rely on that timing ...