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<li class="toctree-l2"><a class="reference internal" href="../concepts/security.html">Security Guidelines</a></li>
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<li class="toctree-l1"><a class="reference internal" href="../general/index.html">General Topics</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../general/helpers.html">Helper Functions</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/common_functions.html">Global Functions and Constants</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/logging.html">Logging Information</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/errors.html">Error Handling</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/caching.html">Web Page Caching</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/ajax.html">AJAX Requests</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/modules.html">Code Modules</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../general/environments.html">Handling Multiple Environments</a></li>
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<li class="toctree-l1"><a class="reference internal" href="../incoming/index.html">Controllers and Routing</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/controllers.html">Controllers</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/routing.html">URI Routing</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/filters.html">Controller Filters</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/message.html">HTTP Messages</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/request.html">Request Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/incomingrequest.html">IncomingRequest Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/content_negotiation.html">Content Negotiation</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/methodspoofing.html">HTTP Method Spoofing</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../incoming/restful.html">RESTful Resource Handling</a></li>
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</ul>
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<li class="toctree-l1"><a class="reference internal" href="../outgoing/index.html">Building Responses</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/views.html">Views</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/view_cells.html">View Cells</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/view_renderer.html">View Renderer</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/view_layouts.html">View Layouts</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/view_parser.html">View Parser</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/table.html">HTML Table Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/response.html">HTTP Responses</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/api_responses.html">API Response Trait</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/localization.html">Localization</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../outgoing/alternative_php.html">Alternate PHP Syntax for View Files</a></li>
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</ul>
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</li>
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</ul>
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<ul class="current">
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<li class="toctree-l1 current"><a class="reference internal" href="index.html">Working With Databases</a><ul class="current">
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<li class="toctree-l2"><a class="reference internal" href="examples.html">Quick Start: Usage Examples</a></li>
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<li class="toctree-l2"><a class="reference internal" href="configuration.html">Database Configuration</a></li>
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<li class="toctree-l2"><a class="reference internal" href="connecting.html">Connecting to a Database</a></li>
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<li class="toctree-l2"><a class="reference internal" href="queries.html">Running Queries</a></li>
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<li class="toctree-l2"><a class="reference internal" href="results.html">Generating Query Results</a></li>
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<li class="toctree-l2"><a class="reference internal" href="helpers.html">Query Helper Functions</a></li>
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<li class="toctree-l2"><a class="reference internal" href="query_builder.html">Query Builder Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="transactions.html">Transactions</a></li>
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<li class="toctree-l2 current"><a class="current reference internal" href="#">Getting MetaData</a></li>
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<li class="toctree-l2"><a class="reference internal" href="call_function.html">Custom Function Calls</a></li>
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<li class="toctree-l2"><a class="reference internal" href="events.html">Database Events</a></li>
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<li class="toctree-l2"><a class="reference internal" href="utilities.html">Database Utilities</a></li>
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</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../models/index.html">Modeling Data</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../models/model.html">Using CodeIgniter's Model</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../models/entities.html">Using Entity Classes</a></li>
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</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../dbmgmt/index.html">Managing Databases</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../dbmgmt/forge.html">Database Manipulation with Database Forge</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../dbmgmt/migration.html">Database Migrations</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../dbmgmt/seeds.html">Database Seeding</a></li>
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</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../libraries/index.html">Library Reference</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/caching.html">Caching Driver</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/curlrequest.html">CURLRequest Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/email.html">Email Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/encryption.html">Encryption Service</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/files.html">Working with Files</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/honeypot.html">Honeypot Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/images.html">Image Manipulation Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/pagination.html">Pagination</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/security.html">Security</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/throttler.html">Throttler</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/time.html">Times and Dates</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/uploaded_files.html">Working with Uploaded Files</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">Working with URIs</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../libraries/validation.html">Validation</a></li>
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</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/filesystem_helper.html">Filesystem Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/test_helper.html">Test Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
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</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../testing/index.html">Testing</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../testing/overview.html">Getting Started</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../testing/database.html">Database</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../testing/fabricator.html">Generating Data</a></li>
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||
<li class="toctree-l2"><a class="reference internal" href="../testing/controllers.html">Controller Testing</a></li>
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||
<li class="toctree-l2"><a class="reference internal" href="../testing/feature.html">HTTP Testing</a></li>
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||
<li class="toctree-l2"><a class="reference internal" href="../testing/benchmark.html">Benchmarking</a></li>
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||
<li class="toctree-l2"><a class="reference internal" href="../testing/debugging.html">Debugging Your Application</a></li>
|
||
</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../cli/index.html">Command Line Usage</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../cli/cli.html">Running via the Command Line</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../cli/cli_commands.html">Custom CLI Commands</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../cli/cli_generators.html">CLI Generators</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../cli/cli_library.html">CLI Library</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../cli/cli_request.html">CLIRequest Class</a></li>
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</ul>
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</li>
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</ul>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="../extending/index.html">Extending CodeIgniter</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="../extending/core_classes.html">Creating Core System Classes</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../extending/common.html">Replacing Common Functions</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../extending/events.html">Events</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../extending/basecontroller.html">Extending the Controller</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../extending/authentication.html">Authentication</a></li>
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<li class="toctree-l2"><a class="reference internal" href="../extending/contributing.html">Contributing to CodeIgniter</a></li>
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</ul>
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<li><a href="../index.html" class="icon icon-home"></a> »</li>
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<li><a href="index.html">Working With Databases</a> »</li>
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||
|
||
<hr/>
|
||
</div>
|
||
<div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
|
||
<div itemprop="articleBody">
|
||
|
||
<div class="section" id="database-metadata">
|
||
<h1>Database Metadata<a class="headerlink" href="#database-metadata" title="Permalink to this headline">¶</a></h1>
|
||
<div class="contents local topic" id="contents">
|
||
<ul class="simple">
|
||
<li><p><a class="reference internal" href="#table-metadata" id="id1">Table MetaData</a></p>
|
||
<ul>
|
||
<li><p><a class="reference internal" href="#list-the-tables-in-your-database" id="id2">List the Tables in Your Database</a></p></li>
|
||
<li><p><a class="reference internal" href="#determine-if-a-table-exists" id="id3">Determine If a Table Exists</a></p></li>
|
||
</ul>
|
||
</li>
|
||
<li><p><a class="reference internal" href="#field-metadata" id="id4">Field MetaData</a></p>
|
||
<ul>
|
||
<li><p><a class="reference internal" href="#list-the-fields-in-a-table" id="id5">List the Fields in a Table</a></p></li>
|
||
<li><p><a class="reference internal" href="#determine-if-a-field-is-present-in-a-table" id="id6">Determine If a Field is Present in a Table</a></p></li>
|
||
<li><p><a class="reference internal" href="#retrieve-field-metadata" id="id7">Retrieve Field Metadata</a></p></li>
|
||
<li><p><a class="reference internal" href="#list-the-indexes-in-a-table" id="id8">List the Indexes in a Table</a></p></li>
|
||
</ul>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
<div class="section" id="table-metadata">
|
||
<h2><a class="toc-backref" href="#id1">Table MetaData</a><a class="headerlink" href="#table-metadata" title="Permalink to this headline">¶</a></h2>
|
||
<p>These functions let you fetch table information.</p>
|
||
<div class="section" id="list-the-tables-in-your-database">
|
||
<h3><a class="toc-backref" href="#id2">List the Tables in Your Database</a><a class="headerlink" href="#list-the-tables-in-your-database" title="Permalink to this headline">¶</a></h3>
|
||
<p><strong>$db->listTables();</strong></p>
|
||
<p>Returns an array containing the names of all the tables in the database
|
||
you are currently connected to. Example:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$tables</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">listTables</span><span class="p">();</span>
|
||
|
||
<span class="k">foreach</span> <span class="p">(</span><span class="nv">$tables</span> <span class="k">as</span> <span class="nv">$table</span><span class="p">)</span>
|
||
<span class="p">{</span>
|
||
<span class="k">echo</span> <span class="nv">$table</span><span class="p">;</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">Note</p>
|
||
<p>Some drivers have additional system tables that are excluded from this return.</p>
|
||
</div>
|
||
</div>
|
||
<div class="section" id="determine-if-a-table-exists">
|
||
<h3><a class="toc-backref" href="#id3">Determine If a Table Exists</a><a class="headerlink" href="#determine-if-a-table-exists" title="Permalink to this headline">¶</a></h3>
|
||
<p><strong>$db->tableExists();</strong></p>
|
||
<p>Sometimes it’s helpful to know whether a particular table exists before
|
||
running an operation on it. Returns a boolean TRUE/FALSE. Usage example:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$db</span><span class="o">-></span><span class="na">tableExists</span><span class="p">(</span><span class="s1">'table_name'</span><span class="p">))</span>
|
||
<span class="p">{</span>
|
||
<span class="c1">// some code...</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">Note</p>
|
||
<p>Replace <em>table_name</em> with the name of the table you are looking for.</p>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="section" id="field-metadata">
|
||
<h2><a class="toc-backref" href="#id4">Field MetaData</a><a class="headerlink" href="#field-metadata" title="Permalink to this headline">¶</a></h2>
|
||
<div class="section" id="list-the-fields-in-a-table">
|
||
<h3><a class="toc-backref" href="#id5">List the Fields in a Table</a><a class="headerlink" href="#list-the-fields-in-a-table" title="Permalink to this headline">¶</a></h3>
|
||
<p><strong>$db->getFieldNames()</strong></p>
|
||
<p>Returns an array containing the field names. This query can be called
|
||
two ways:</p>
|
||
<p>1. You can supply the table name and call it from the $db->
|
||
object:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$fields</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">getFieldNames</span><span class="p">(</span><span class="s1">'table_name'</span><span class="p">);</span>
|
||
|
||
<span class="k">foreach</span> <span class="p">(</span><span class="nv">$fields</span> <span class="k">as</span> <span class="nv">$field</span><span class="p">)</span>
|
||
<span class="p">{</span>
|
||
<span class="k">echo</span> <span class="nv">$field</span><span class="p">;</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>2. You can gather the field names associated with any query you run by
|
||
calling the function from your query result object:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$query</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">query</span><span class="p">(</span><span class="s1">'SELECT * FROM some_table'</span><span class="p">);</span>
|
||
|
||
<span class="k">foreach</span> <span class="p">(</span><span class="nv">$query</span><span class="o">-></span><span class="na">getFieldNames</span><span class="p">()</span> <span class="k">as</span> <span class="nv">$field</span><span class="p">)</span>
|
||
<span class="p">{</span>
|
||
<span class="k">echo</span> <span class="nv">$field</span><span class="p">;</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
</div>
|
||
<div class="section" id="determine-if-a-field-is-present-in-a-table">
|
||
<h3><a class="toc-backref" href="#id6">Determine If a Field is Present in a Table</a><a class="headerlink" href="#determine-if-a-field-is-present-in-a-table" title="Permalink to this headline">¶</a></h3>
|
||
<p><strong>$db->fieldExists()</strong></p>
|
||
<p>Sometimes it’s helpful to know whether a particular field exists before
|
||
performing an action. Returns a boolean TRUE/FALSE. Usage example:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$db</span><span class="o">-></span><span class="na">fieldExists</span><span class="p">(</span><span class="s1">'field_name'</span><span class="p">,</span> <span class="s1">'table_name'</span><span class="p">))</span>
|
||
<span class="p">{</span>
|
||
<span class="c1">// some code...</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">Note</p>
|
||
<p>Replace <em>field_name</em> with the name of the column you are looking
|
||
for, and replace <em>table_name</em> with the name of the table you are
|
||
looking for.</p>
|
||
</div>
|
||
</div>
|
||
<div class="section" id="retrieve-field-metadata">
|
||
<h3><a class="toc-backref" href="#id7">Retrieve Field Metadata</a><a class="headerlink" href="#retrieve-field-metadata" title="Permalink to this headline">¶</a></h3>
|
||
<p><strong>$db->getFieldData()</strong></p>
|
||
<p>Returns an array of objects containing field information.</p>
|
||
<p>Sometimes it’s helpful to gather the field names or other metadata, like
|
||
the column type, max length, etc.</p>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">Note</p>
|
||
<p>Not all databases provide meta-data.</p>
|
||
</div>
|
||
<p>Usage example:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$fields</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">getFieldData</span><span class="p">(</span><span class="s1">'table_name'</span><span class="p">);</span>
|
||
|
||
<span class="k">foreach</span> <span class="p">(</span><span class="nv">$fields</span> <span class="k">as</span> <span class="nv">$field</span><span class="p">)</span>
|
||
<span class="p">{</span>
|
||
<span class="k">echo</span> <span class="nv">$field</span><span class="o">-></span><span class="na">name</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$field</span><span class="o">-></span><span class="na">type</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$field</span><span class="o">-></span><span class="na">max_length</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$field</span><span class="o">-></span><span class="na">primary_key</span><span class="p">;</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>If you have run a query already you can use the result object instead of
|
||
supplying the table name:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$query</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">query</span><span class="p">(</span><span class="s2">"YOUR QUERY"</span><span class="p">);</span>
|
||
<span class="nv">$fields</span> <span class="o">=</span> <span class="nv">$query</span><span class="o">-></span><span class="na">fieldData</span><span class="p">();</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>The following data is available from this function if supported by your
|
||
database:</p>
|
||
<ul class="simple">
|
||
<li><p>name - column name</p></li>
|
||
<li><p>max_length - maximum length of the column</p></li>
|
||
<li><p>primary_key - 1 if the column is a primary key</p></li>
|
||
<li><p>type - the type of the column</p></li>
|
||
</ul>
|
||
</div>
|
||
<div class="section" id="list-the-indexes-in-a-table">
|
||
<h3><a class="toc-backref" href="#id8">List the Indexes in a Table</a><a class="headerlink" href="#list-the-indexes-in-a-table" title="Permalink to this headline">¶</a></h3>
|
||
<p><strong>$db->getIndexData()</strong></p>
|
||
<p>Returns an array of objects containing index information.</p>
|
||
<p>Usage example:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$keys</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">getIndexData</span><span class="p">(</span><span class="s1">'table_name'</span><span class="p">);</span>
|
||
|
||
<span class="k">foreach</span> <span class="p">(</span><span class="nv">$keys</span> <span class="k">as</span> <span class="nv">$key</span><span class="p">)</span>
|
||
<span class="p">{</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">name</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">type</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">fields</span><span class="p">;</span> <span class="c1">// array of field names</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>The key types may be unique to the database you are using.
|
||
For instance, MySQL will return one of primary, fulltext, spatial, index or unique
|
||
for each key associated with a table.</p>
|
||
<p><strong>$db->getForeignKeyData()</strong></p>
|
||
<p>Returns an array of objects containing foreign key information.</p>
|
||
<p>Usage example:</p>
|
||
<div class="highlight-html+php notranslate"><div class="highlight"><pre><span></span><span class="nv">$keys</span> <span class="o">=</span> <span class="nv">$db</span><span class="o">-></span><span class="na">getForeignKeyData</span><span class="p">(</span><span class="s1">'table_name'</span><span class="p">);</span>
|
||
|
||
<span class="k">foreach</span> <span class="p">(</span><span class="nv">$keys</span> <span class="k">as</span> <span class="nv">$key</span><span class="p">)</span>
|
||
<span class="p">{</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">constraint_name</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">table_name</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">column_name</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">foreign_table_name</span><span class="p">;</span>
|
||
<span class="k">echo</span> <span class="nv">$key</span><span class="o">-></span><span class="na">foreign_column_name</span><span class="p">;</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>The object fields may be unique to the database you are using. For instance, SQLite3 does
|
||
not return data on column names, but has the additional <em>sequence</em> field for compound
|
||
foreign key definitions.</p>
|
||
</div>
|
||
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|
||
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|
||
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