Câu hỏi phỏng vấn MySQL
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What is autocommit in MySQL? Can you run a...

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What is Autocommit in MySQL?

Autocommit in MySQL is a mode where each SQL statement forms a complete transaction on its own. By default, MySQL operates with autocommit mode enabled. This means that as soon as a statement is executed, MySQL automatically commits it, making the changes permanent in the database. This behavior ensures that each individual operation is atomic, which means it either fully completes or does not happen at all, without any intermediate states being visible to other transactions[3][5][7][9][10].

Running Transactions with Autocommit Enabled

It is indeed possible to run transactions without disabling autocommit, although the behavior of transactions changes slightly depending on whether autocommit is enabled or disabled.

When autocommit is enabled, MySQL still allows the use of transaction control statements like START TRANSACTION, COMMIT, and ROLLBACK. Starting a transaction with START TRANSACTION effectively suspends the autocommit behavior until the transaction is explicitly committed or rolled back. This means that even with autocommit enabled, you can group several statements into a single transaction that will not be committed until you issue a COMMIT command, or that can be entirely discarded with a ROLLBACK command[1][3][6][8][13].

However, it's important to note that certain statements in MySQL cause an implicit commit, which can affect the behavior of transactions. For example, Data Definition Language (DDL) statements like CREATE, ALTER, and DROP will commit the transaction they are part of, regardless...

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