-530: Referential
integrity violated 
Explanation:
The following reasons are possible:
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An INSERT or UPDATE-statement issued on a table that is the referencing table in a referential CONSTRAINT definition produces a row that is not a matching row of the CONSTRAINT definition.
When deleting rows from a referenced table (referenced_table) of a referential CONSTRAINT definition with ON DELETE RESTRICT in the DELETE RULE, a matching row exists.
User Action:
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Display the definition of the referential CONSTRAINT definition using a QUERY statement issued on the system table DOMAIN.FOREIGNKEYCOLUMNS. Change the INSERT or UPDATE statement according to this definition.
Use an appropriate QUERY statement to find out which row of the referencing table prevents the desired referenced table rows from being deleted.