[Java lista] Jasper report mezőbe SQL query?

[Auth Gábor]

Halihó!

Gergely Hodicska írta 00.11:
>> és még performace-ra is király lesz
> Ez a fajta subquery kiváltható joinnal, ami gyorsabb is lesz.

javaforum_test=> SELECT COUNT(*) FROM stat;
  count
---------
 2058678
(1 row)

javaforum_test=> SELECT COUNT(*) FROM session_table;
  count
---------
 2573642
(1 row)

javaforum_test=> \timing
Timing is on.
javaforum_test=> \o /tmp/stat
javaforum_test=> SELECT st.created,(SELECT se.ip FROM session_table AS se 
WHERE id=st.session_fk) AS ip FROM stat AS st;
Time: 18789,598 ms
javaforum_test=> SELECT st.created,se.ip FROM stat AS st INNER JOIN 
session_table AS se ON (st.session_fk=se.id);
Time: 51082,160 ms
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