Programming

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To perform a contains search in Redis, you can use the SCAN command along with the MATCH pattern. This command allows you to iterate over keys in the database that match a specified pattern. For example, if you want to find all keys that contain a specific substring, you can use the pattern "*substring*".Additionally, you can also use Redis sorted sets or sets to store values that you want to search for.
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To update a sorted set in Redis with the values of another sorted set, you can use the ZUNIONSTORE command. This command calculates the union of multiple sorted sets and stores the result in a new sorted set. You can use this command to update an existing sorted set with the values from another sorted set by specifying the keys of the sorted sets to be unioned and the key of the resulting sorted set.
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To delete all keys from a Redis cluster, you can use the FLUSHALL command. This command will remove all keys from all databases in the cluster. However, please be cautious when using this command as it will permanently delete all data stored in the cluster. Make sure to backup any important data before proceeding with this operation. Additionally, keep in mind that this operation may have a significant impact on the performance of the cluster, especially if it contains a large number of keys.
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To identify Redis keys from the redis-cli monitor command, you can observe the output of the command to see the operations being performed on different keys in the Redis database. The key names will be displayed as part of the command along with the specific operation being executed on the key, such as SET, GET, DEL, etc. By monitoring the commands in real-time, you can identify the keys based on the operations being performed on them.
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To set up a Docker Redis container with SSL, you will first need to create a self-signed SSL certificate for Redis. You can do this using tools like OpenSSL. Then, you need to configure the Redis server to use SSL by setting the 'tls-port' and 'tls-cert-file' and 'tls-key-file' options in the Redis configuration file.Next, you will need to create a Dockerfile for building the Redis image with the SSL configuration.
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To sync an operation between Redis and MongoDB, you can use a technique called change data capture (CDC). This involves capturing changes made to the data in MongoDB and then applying those changes to Redis in real-time.One way to implement CDC is to use a tool like Kafka or Debezium to capture changes in MongoDB and then write them to Redis. Another approach is to write custom code that listens for changes in MongoDB and updates Redis accordingly.
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In Redis, you can update dependent key values by using the concept of transactions with the help of the MULTI and EXEC commands.First, you need to start a transaction by using the MULTI command. This command tells Redis that a series of commands needs to be executed atomically.Next, you can update the dependent key values by using regular Redis commands like SET, GET, INCR, etc.Once you have updated all the dependent key values, you can commit the transaction by using the EXEC command.
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Redis supports up to 32,767 channels for publishing and subscribing using the Pub/Sub feature. This means that clients can subscribe to this many different channels concurrently, allowing for efficient and scalable messaging between clients and servers.[rating:ce821fa8-0cbe-48d4-a522-252e94dac366]What is the purpose of pub/sub channels in Redis?The purpose of pub/sub channels in Redis is to provide a messaging system where clients can subscribe to and receive messages from different channels.
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To implement auto-refresh with Redis cache, you can use Redis' built-in features such as keyspace notifications or expiration policies. By setting a time-to-live (TTL) for your cached data and configuring Redis to automatically refresh the data when it expires, you can ensure that your cache remains up-to-date without manual intervention. Keyspace notifications can notify your application when a specific key's value changes, allowing you to refresh the cache accordingly.
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When using the scan_iter() function in Redis, you can exclude keys by providing a pattern to match keys that should be excluded. This pattern should be passed as an argument to the function. For example, if you want to exclude keys that start with "foo", you can pass the pattern "foo*" to scan_iter(). This will ensure that only keys that do not match the pattern will be returned by the iterator.