Challenging and urgent

Question

I have tables like this and requirement is given below
table a
specid specifications
1 aa
2 bb
3 cc
4 dd
5 ee
6 ff
7 gg
8 hh
9 ii
10 jj
table b
specid parent_specid table_name titleid
1 2 t1 1234
3 2 t1 1234
3 2 t1 1234
3 2 t2 1235
3 2 t2 1236
4 2 t3 1237
4 2 t4 1237
5 2 t4 1237
5 2 t5 1234
1 3 t6 1235
i want the table_name,key based on the specifications(from table a) i.e
select table_name,key from b where (specid parent_specid) in (select specification from a where specification in ('aa','hh') --this is not working
note:= here 'hh' is the parent to the 'aa' and look at "table b" for parent child relation.
note:= currently i am using 10g

Answer 1

I am unable to comprehend your query:
select table_name,key from b where (specid, parent_specid) in (select specifications from a where specification in ('aa','hh')since,
1. you are equating multiple columns i.e. (specid, parent_specid) against a single column value (specifications) using "IN"
2. table a.specifications contains varchar2 values as 'aa','bb' etc.. whereas specid, parent_specid containts numeric values as 1,2,3 etc.
hence, I am unable to decipher the intended output using the query that you have provided as a reference. This is why, I had requested and I still request you to provide the intended output (sample data) based on the table values that you have provided so that we can come up with a more meaningful query to address your requirement.
Thanks