How to write selfjoin query?

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1.00/5 (1 vote)

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MID -- Name-- PID
2 ---- A ----- 0
3 ---- M ----- 0
4 ---- N ----- 0
11 --- B ----- 2
12 --- C ----- 2
13 --- D ----- 3
14 --- E ----- 2
31 --- Z ---- 11
32 --- Y ---- 12
33 --- X ---- 12
34 --- W ---- 13
35 --- V ---- 14

Above is the table structure.
I want to write a single query (where condition will be PID=2) from which this following value will be fetched

11
12
14
31
32
33
35

Can anyone help me to write this query?
Thanks in advance.

Posted 29-Jun-12 18:50pm

sahabiswarup

Updated 29-Jun-12 18:51pm

v2

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pankaj hirapara · Answer 1 · 2012-06-29T18:56:00

Solution 1

select t1.MID from tablename as t1
join tablename as t2 on t1.PID = t2.PID
where t1.PID = 2

Posted 29-Jun-12 18:56pm

pankaj hirapara

Comments

Prosan 30-Jun-12 1:03am

my 5

sahabiswarup 30-Jun-12 1:47am

you skip my table record..i want to fetch records where PID=2
and then select those MID ie 11,12,14
and then select MID where PID 11,12,14

then finally i'll get
11
12
14
31
32
33
35

Prosan · Answer 2 · 2012-06-29T19:03:00

Solution 2

SQL

select Mid from urtable where pid=2

what problem in query. it will give you same result. no need of selfjoin if you want to write self join query use solution 1.

Posted 29-Jun-12 19:03pm

Prosan

Comments

sahabiswarup 30-Jun-12 1:49am

first of all select MID where PID=2
then result will be 11,12,14
Then select MID where PID=11,12,14
then result will be 31,32,33,35
so finally the result will be
11 12 14 31 32 33 35
got it?