When Redis and MySQL data are inconsistent, the processing method should take corresponding measures according to the reason: check the consistency rules and clarify the master-copy relationship of the data source. A compensation mechanism is adopted to initiate asynchronous writing to MySQL and callback verification after the Redis writing is completed. Use transactions to operate Redis and MySQL simultaneously to ensure atomicity. Regularly synchronize Redis data to MySQL to ensure data consistency. Consider using distributed locks to ensure the order of operations.
How to deal with data inconsistencies between Redis and MySQL
Redis and MySQL are two different data storage systems. Have different characteristics in terms of data consistency. When there is inconsistency between the two data, appropriate measures need to be taken to deal with it.
Cause Analysis
The reasons for the inconsistency between Redis and MySQL data may be various, including:
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Writing Different order: Since Redis and MySQL are independent systems, the order of write operations may be inconsistent.
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Cache expiration: Redis serves as a cache, and data has an expiration time. When MySQL data is updated, if the data in Redis has not expired, inconsistency will occur.
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Parallel writing: When multiple threads or processes write data at the same time, data in Redis and MySQL may be inconsistent.
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Network delay: The network delay between Redis and MySQL may cause data to be updated untimely, resulting in inconsistency.
Processing method
To solve the problem of data inconsistency between Redis and MySQL requires different processing methods according to the specific situation:
- Check consistency rules: Clearly define the rules for Redis and MySQL data consistency, such as who is the primary data source and who is the replica.
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Adopt a compensation mechanism: After the Redis write operation is completed, an asynchronous write request is issued to MySQL and callback verification is performed.
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Use transactions: Execute transactions simultaneously in Redis and MySQL to ensure atomicity.
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Regular synchronization: Regularly synchronize Redis data to MySQL to ensure data consistency.
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Consider using distributed locks: When writing Redis and MySQL data, use distributed locks to ensure the order of operations.
Best Practices
In order to avoid data inconsistency between Redis and MySQL, it is recommended to follow the following best practices:
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Use Redis as cache: Store frequently accessed data in Redis to avoid frequent queries to MySQL.
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Set a reasonable cache expiration time: Avoid data inconsistency due to cache expiration.
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Use transactions as much as possible: Use transactions when updating Redis and MySQL data at the same time.
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Regular data checking: Regularly check the data in Redis and MySQL, and repair inconsistencies in a timely manner.
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