oracle query for get 20 top agency which have pass issued - sql

Question

I have a query which show datewise pass issued by agency. I wanted to get top 20 agency who have most pass issued here is my query

Answer 1

Nothing in your data id identifies "agency". If I assume you mean "agent", you can get the top 20 by aggregating and then limiting the result. In Oracle 12C+, you can use:
SELECT gp.agent_id, a.agent_name, COUNT(*)
FROM eofficeuat.gatepass gp INNER JOIN
eofficeuat.cnf_agents a
ON gp.agent_id = a.agent_id INNER JOIN
eofficeuat.cardprintlog_user u
ON gp.agent_id = u.agent_id
WHERE gp.issuedatetime BETWEN DATE '2019-09-28' AND DATE '2019-09-29'
GROUP BY gp.agent_id, a.agent_name
ORDER BY COUNT(*) DESC
FETCH FIRST 1 ROW ONLY;
In earlier versions, a subquery is needed:
SELECT *
FROM (SELECT gp.agent_id, a.agent_name, COUNT(*)
FROM eofficeuat.gatepass gp INNER JOIN
eofficeuat.cnf_agents a
ON gp.agent_id = a.agent_id INNER JOIN
eofficeuat.cardprintlog_user u
ON gp.agent_id = u.agent_id
WHERE gp.issuedatetime BETWEEN DATE '2019-09-28' AND DATE '2019-09-29'
GROUP BY gp.agent_id, a.agent_name
ORDER BY COUNT(*) DESC
) a
WHERE rownum <= 20;
Obviously, if you do mean "agency" and that is identified by different columns, you would just adjust the SELECT and GROUP BY clauses.
Also, I would advise you never to use BETWEEN on dates in Oracle. There is a time component that might cause issues.
If you intend only times on '2019-09-28', then:
gp.issuedatetime >= DATE '2019-09-28' AND
gp.issuedatetime < DATE '2019-09-29'
If you intend both the 28th and 29th:
gp.issuedatetime >= DATE '2019-09-28' AND
gp.issuedatetime < DATE '2019-09-30'

Answer 2

You can use LIMIT clause(12c or higher version) with TOP 20 records as following:
SELECT eofficeuat.gatepass.agent_id, eofficeuat.cnf_agents.agent_name, COUNT(1) as cnt
FROM eofficeuat.gatepass INNER JOIN
eofficeuat.cnf_agents
ON eofficeuat.gatepass.agent_id = eofficeuat.cnf_agents.agent_id INNER JOIN
eofficeuat.cardprintlog_user
ON eofficeuat.gatepass.agent_id = eofficeuat.cardprintlog_user.agent_id
WHERE eofficeuat.gatepass.issuedatetime BETWEN DATE '2019-09-28' AND DATE '2019-09-29'
GROUP BY eofficeuat.gatepass.agent_id, eofficeuat.cnf_agents.agent_name
ORDER BY cnt DESC
FETCH FIRST 20 ROWS ONLY; -- this will fetch top 20 agents
Cheers!!