Some way to list all constraints?

Maybe this is another one of those "System Table" things...to which I have no access...

I'm trying to clean out a DB so I can use it for testing a load routine but keep getting hit with "Unable to delete because of...(whatever constraint). In SQL Programmer I can view constraints on a table-by-table basis, but it seems like there should be some way for me to just list them all along with the table involved in each so I can just refer to the list instead of trying to guess the table.

?

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PeteCresswell