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<td><h1>Code Igniter User Guide Version 1.5.0</h1></td>
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Database Caching Class
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<h1>Database Caching Class</h1>
<p>The Database Caching Class contains functions that permit you to cache your queries.</p>
<p class="important"><strong>Important:</strong> This class is initialized automatically by the database driver
when caching is enabled, so you do NOT need to load this class manually.
More info below...</p>
<h2>How Does Caching Work?</h2>
<p>When caching is enabled, anytime you run a "read" type query (SELECT) the result object will
be serialized and stored in a text file. Subsequent calls to that query will use the result from the cache file
rather then accessing your database.</p>
<p>Code Igniter places your cached queries into sub-folders that are named based on the URI request. This allows
identical queries
<p>If you run a "write" type query (INSERT, UPDATE, etc.)
<p>Although caching queries reduces your database load, cached queries do require more
file-system operations, as cache files are created and read. Instead of accessing your database for information
text files are used.
Whether you see a performance gain as a result of caching is dependant on many factors.
For example, if you have a highly optimized database under very little load, you probably won't see a performance boost.
If your database is under heavy use you probably will see an improved response, assuming your filesystem is not
overly taxed.</p>
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