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mediumDSA

What is an UPSERT?

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01

Understand the problem

Explain UPSERT.

upsert
02

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03

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An UPSERT inserts a row or updates it if it already exists. Postgres uses INSERT ... ON CONFLICT (key) DO UPDATE, MySQL INSERT ... ON DUPLICATE KEY UPDATE, and the SQL standard MERGE. It avoids race conditions of check-then-insert.

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04

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SQLUPSERT Playground
05

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Dossier 36 of 70 decoded in the SQL track. One more won't hurt.

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