Actually, if you perform an INSERT which results in a duplicate key error, then by definition you must know the key already. How else could you have inserted that record otherwise?

The last_insert_id is only useful with auto-incrementing keys (and even then I find it rarely needed), but in any case auto-incrementing keys should never give a duplicate key error.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

In reply to Re^4: return primary key if duplicate entry exists? by CountZero
in thread return primary key if duplicate entry exists? by diyaz

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