sql - JDBC constraint exception details -


i'm using jdbc persist data sql server , want insert new row table has primary key, several foreign keys, , several uniqueness constraints on various columns. wondering how handle constraint violations can identify fields need corrected (in order report meaningful user).

e.g:

table test: id (primary), fk_id (foreign key), field1 (unique), field2 (unique)

inserting duplicate value in field1 or field2 gives: 

errorcode: 2627 sqlstate: 23000 violation of unique key constraint '<unique constraint name>'. cannot insert duplicate key in object 'dbo.test'. duplicate key value (<value>).

however, isn't enough determine field caused exception (so can tell user, correct field1 or field2), short of parsing error message , using constraint name (which doesn't feel right , seems brittle solution).

the other way can think of not rely on exceptions , instead query existing rows same value (manually checking uniqueness before insertion). however, requires potentially many queries in serializable transaction (reducing concurrency). worse, transaction can deadlock , rollback if timing unfortunately conflicts transaction.

is there better way achieve i'm trying without having parse (locale specific) exception messages? 'best practice' way?


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