Unmaching documents from 3 child tables

[ovidiucotarlea]

Hi, this is my problem:
I have a parent table and 3 child tables and i want to find all the unmatching documents from the parent table.

thank you

 

[fluteplr]

Please provide table structures and relation information

 

[carp]

If you mean you need to find all of the rows in the parent table that have no child rows, you could try

SELECT p_identifier FROM parent_table
WHERE p_identifier NOT IN (SELECT c1_identifier FROM child1)
AND p_identifier NOT IN (SELECT c2_identifier FROM child2)
AND p_identifier NOT IN (SELECT c3_identifier FROM child3);

However, this may take awhile, depending on the sizes of your tables.