On 8/24/05 9:46 AM, "Josep Sanmartí" <[EMAIL PROTECTED]> wrote:
> Hello, > I have a 'big' problem: > I have the following table users(name, start_time, end_time), a new row > is set whenever a user logs into a server. I want to know how many > users have logged in EVERYDAY between 2 different dates. The only idea > that I have is making several select (one for each day): > SELECT COUNT(name) FROM users WHERE start_time between "startDate" > and "startDate+1" > SELECT COUNT(name) FROM users WHERE start_time between "startDate+1" > and "startDate+2" > ... > I would like to know if its possible to make it in 1 sql statement or > just which is the best efficient way to solve it. > By the way, I use Postgres 7.4. See: http://www.postgresql.org/docs/8.0/interactive/sql-select.html#SQL-UNION like: SELECT COUNT(name) FROM users WHERE start_time between "startDate" and "startDate+1" union SELECT COUNT(name) FROM users WHERE start_time between "startDate+1" and "startDate+2" Sean ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
