How to handle redis transactions
Redis transaction processing
A Redis transaction is a grouping of commands that are either executed or all of them are not executed. It ensures atomicity, consistency, isolation and persistence (ACID) properties, even in concurrency.
How transactions work:
- Start a transaction: Use the
MULTI
command to start a transaction. - Record command: Execute any number of Redis commands in a transaction.
- Commit or rollback transactions: Use the
EXEC
command to submit a transaction orDISCARD
command to roll back the transaction.
Submit and rollback:
- Commit: If there are no errors in the transaction, the transaction is submitted through the
EXEC
command, and all commands are applied atomically to the database. - Rollback: If any error occurs in the transaction, the transaction is rolled back through the
DISCARD
command, all commands will be discarded and the database state remains unchanged.
Isolation:
Redis transactions provide isolation, which means that transactions executed concurrently do not interfere with each other. When a transaction is executing, modifications to the data accessed by the transaction in the database will be blocked until the transaction is committed or rolled back.
Persistence:
Redis transactions do not provide persistence. This means that if the Redis server fails after the transaction is committed, modifications to the transaction will be lost. To ensure persistence, you can use Redis persistence features (such as RDB or AOF).
Notes:
- Commands in transactions must not modify keys locked by other transactions.
- Transactions cannot span multiple Redis instances.
- Transactions cannot be nested.
- Transactions may be automatically terminated due to a Redis server timeout.
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