INSERT ON DUPLICATE KEY: How Can I Ignore Duplicate Inserts in SQL?

INSERT ON DUPLICATE KEY: Maintaining Data Integrity

In database management, it is essential to handle scenarios involving duplicate data efficiently. One option is to prevent duplicate insertions by defining unique keys. However, in some cases, it may be desirable to simply disregard duplicate inserts without generating an error.

Considering the provided table structure and the need to add a row only if the key does not exist, the following issue arises:

Problem: Is there a syntax similar to "INSERT ... ON DUPLICATE KEY DO NOTHING"?

The answer is affirmative:

Solution 1: INSERT ... ON DUPLICATE KEY UPDATE>

This syntax ensures that no update is performed on the row, even though the id is reassigned to itself. This effectively results in ignoring duplicate inserts.

However, if errors (e.g., conversion errors, foreign key errors) or the potential exhaustion of an autoincrement field are not of concern, an alternative approach can be used:

Solution 2: INSERT IGNORE INTO ...

This syntax completely ignores rows that would have resulted in a duplicate key error, effectively achieving the desired behavior of adding the row if it does not already exist and silently ignoring it otherwise.

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