[development] SQL Query Doubt

[Ivan Sergio Borgonovo]

On Sat, 16 Apr 2011 04:24:35 -0700
Jason Flatt <drupal at oadaeh.net> wrote:


> SELECT EmployeeID FROM {tablename} WHERE Skill = 'PHP' AND Skill =
> 'Java';

So 'Java' = 'PHP', interesting.

create table test.employee (eid int, skill varchar (15), primary key
(eid, skill));

select * from test.employee;
1;"PHP"
1;"SQL"
1;"Java"
1;"VoIP"
2;"Shell Scripting"
2;"PHP"
2;"Java"
3;"C++"
3;"PHP"
3;"Pearl"

data sample is a bit different to check employee 3 doesn't get
selected.

select t1.eid from test.employee t1
  join test.employee t2 on t1.eid=t2.eid
  where t1.skill='Java' and t2.skill='PHP'
  group by t1.eid
;
1
2







-- 
Ivan Sergio Borgonovo
http://www.webthatworks.it