Catching Specific Exception question...

[bmgmzp]

How would I catch a specific exception? For instance I have a table with a compound primary key... the primary key is not an auto increment but I dont want to allow duplicates to be inserted. When I try to insert a duplicate it throws an exception, naturally. I am able to trap the SQLException but I'm not sure how to catch that specific 'Violation of PRIMARY KEY constraint'...

Should I query the table before I attempt the insert instead of trying to catch the exception?

 

[ThatRickGuy]

If you can find the exception type, you can catch it by that type. So do a standard try/catch exc as exception and try putting in a bad key. When you hit the catch block, in the debug window type ?exc.gettype() that should get you the type you want to catch. then you can use:

try
  '...
catch excInvalidPrimaryKry as [InvalidKeyException]
  'handle the bad key here
catch exc as exception
  'handle all other errors here
end try

The debate between catching or checking is performance based. Handling exceptions require the stack to be parsed, which is memory intensive and takes a few cycles. But querying the database usually includes network traffic and I/O waits, which are usually slower. So I would stick with the try/catch in this case.

-Rick

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I believe in killer coding ninja monkeys.

 

[chiph]

SQLException

The type of exception object is limit of granularity that you can do with the support of the compiler. If you want to catch your specific SQLException message, you'll have to inspect it via code that you write yourself.

Chip H.


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