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7 min readTo decrease the default number of databases in Redis, you can modify the databases parameter in the Redis configuration file (redis.conf). By default, Redis is configured to have 16 databases (numbered from 0 to 15). To reduce the number of databases, you can change the value of databases to the desired number (e.g. databases 8). Remember to save and restart Redis after making the changes to apply the new configuration.
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5 min readTo parse an online JSON dictionary source in Swift, you can use the URLSession class to retrieve the JSON data from the online source. Once you have retrieved the data, you can use the JSONSerialization class to parse the JSON data into a Swift dictionary. First, create a URL object with the URL of the online JSON source. Then, create a URLSession object and use the dataTask method to create a data task that retrieves the JSON data from the URL.
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5 min readTo fetch a limited result set from a Redis database, you can use the LRANGE command which retrieves a range of elements from a list. This command takes the key of the list, the starting index, and the ending index as parameters to specify the range of elements to retrieve. By specifying the starting and ending indexes, you can fetch a limited number of results from the list stored in the Redis database.
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5 min readIn Swift, optional parameters can be created on a struct by declaring them as optional using the "?" symbol after the data type. This allows the parameter to have a default value of nil if no value is provided when initializing an instance of the struct. Optional parameters can be useful when certain properties are not required for all instances of the struct or when the value may not be known at the time of initialization.
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6 min readTo run Docker Redis in cluster mode, you can use the official Redis Docker image and configure it to run in cluster mode. To do this, you will need to create a Docker network for the Redis cluster containers to communicate with each other. Then, you can start multiple Redis containers with the --cluster-enabled yes option and specify the cluster-config-file parameter to point to a shared configuration file.
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4 min readTo change the height of a table dynamically in Swift, you can do so by implementing the UITableViewDelegate method tableView(_: heightForRowAt:). This method allows you to specify a custom height for each row in the table based on certain conditions or data.In this method, you can calculate and return the desired height for a specific row based on your requirements. You can access the data for that row and adjust the height accordingly.
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6 min readWhen handling concurrent updates to a Redis key, it is important to ensure that each update operation is atomic and does not result in data loss or corruption. One way to achieve this is by using Redis commands that support optimistic locking, such as WATCH and MULTI/EXEC.The WATCH command allows you to monitor one or more keys for changes during a transaction.
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8 min readWhen encountering undefined symbol errors in Swift, there are several possible solutions you can try. One common cause of this error is missing or inconsistent framework/library dependencies. Make sure that all required frameworks and libraries are correctly linked to your project.Another possible solution is to clean the build folder and rebuild your project. This can help resolve any build errors or inconsistencies that may be causing the undefined symbol error.
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6 min readTo use Redis as session caching in Laravel, first make sure that Redis is installed and running on your server. Then, update your .env file to set the SESSION_DRIVER to "redis" and specify the REDIS_HOST, REDIS_PASSWORD, and REDIS_PORT if necessary.Next, update your session.php configuration file to use the Redis session driver. You can configure options such as the Redis database index and connection configuration here.
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5 min readTo pass an optional<vector<optional>> from C++ to Swift, you can create a bridging function in your C++ code that converts the data structure to a format that Swift can understand. You can use std::vector and std::optional in C++ to represent the data, and then convert it to an NSArray or other Swift-compatible data structure before passing it to Swift. Make sure to handle any potential null values or missing data appropriately to avoid crashes in your Swift code.
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5 min readTo configure Redis as a cache in Rails, you need to first install the Redis gem in your Rails application. You can do this by adding the gem 'redis' to your Gemfile and running bundle install.Next, you need to configure Rails to use Redis as the cache store. You can do this by editing the config/environments/production.rb file and adding the following line:config.cache_store = :redis_store, { host: 'localhost', port: 6379, db: 0, namespace: "cache", expires_in: 90.