comparing two tables

[MORALBAROMETER]

Hi all,
I have two tables that are not link. But their content are
interrelated. I want to find out what is in one table that is not in
the other and vice-versa. how can archieve this in c# or within the
database.
thanks

 

[Andy Bates]

If the tables are in SQL then probably let the database do the hard work.

I assume that there is some common key between the two tables (identifier).
If you had two tables called T1 and T2 and ID was the common key then:

SELECT * FROM T1 WHERE T1.ID NOT IN (SELECT ID FROM T2)

Would return all of the records in T1 that are not in T2. Just swap the
table names above to invert this.

Would probably make sense to ensure that there was an index on the ID column
in each table to speed up the join.

HTH

- Andy

 

[Saber S.]

It is not a C# issue,You can do it using a simple sql query,

Something like it:

Select * From T1 Where ID Not In (Select ID From T2)

 

[MORALBAROMETER]

Thanks alot. The tables have not common key. their keys are dereived
from same table.

 

[MORALBAROMETER]

Thanks alot. The tables have not common key. their keys are dereived
from same table.

 

[Andy Bates]

Not sure I follow you; so what fields do the two tables have in common (or
how can they be linked via another table if necessary)?

- Andy