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MediaWiki has a special page, Special:Redirect, which allows users to view the page, revision, or user associated with a particular ID. Your task is to add functionality which redirects users to a log entry according to the log ID.

Here is one possible way to implement this:

• Query the database for all log entries with the same timestamp as the requested log entry. (This can be done using nested SELECT queries. As this is a fairly advanced database query, I will help you with it.)
• If no log entries are returned, display an error.
• If there is more than one log entry, narrow them down based on log_type first, then log_action, then log_user, then log_namespace and log_title, as far as is required until there is only one log entry remaining.
• Display that log entry (or log entries, if more than one) to the user by redirecting them to Special:Log with the necessary URL parameters.

The database schema for the logging table can be viewed at MediaWiki.org.

More details at https://phabricator.wikimedia.org/T71107. (Another user uploaded a patch to that task in 2014, but their implementation is poor. In particular, it prevents paging to nearby log entries, which is often very important. You should start from scratch.)