wangsaitao
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guotianyun-sp-yh


			
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  <div class="section" id="database-utility-class">
<h1>Database Utility Class<a class="headerlink" href="#database-utility-class" title="Permalink to this headline">¶</a></h1>
<p>The Database Utility Class contains methods that help you manage your
database.</p>
<div class="contents local topic" id="contents">
<ul class="simple">
<li><a class="reference internal" href="#initializing-the-utility-class" id="id1">Initializing the Utility Class</a></li>
<li><a class="reference internal" href="#using-the-database-utilities" id="id2">Using the Database Utilities</a><ul>
<li><a class="reference internal" href="#retrieve-list-of-database-names" id="id3">Retrieve list of database names</a></li>
<li><a class="reference internal" href="#determine-if-a-database-exists" id="id4">Determine If a Database Exists</a></li>
<li><a class="reference internal" href="#optimize-a-table" id="id5">Optimize a Table</a></li>
<li><a class="reference internal" href="#repair-a-table" id="id6">Repair a Table</a></li>
<li><a class="reference internal" href="#optimize-a-database" id="id7">Optimize a Database</a></li>
<li><a class="reference internal" href="#export-a-query-result-as-a-csv-file" id="id8">Export a Query Result as a CSV File</a></li>
<li><a class="reference internal" href="#export-a-query-result-as-an-xml-document" id="id9">Export a Query Result as an XML Document</a></li>
</ul>
</li>
<li><a class="reference internal" href="#backup-your-database" id="id10">Backup Your Database</a><ul>
<li><a class="reference internal" href="#database-backup-notes" id="id11">Database Backup Notes</a></li>
<li><a class="reference internal" href="#usage-example" id="id12">Usage Example</a></li>
<li><a class="reference internal" href="#setting-backup-preferences" id="id13">Setting Backup Preferences</a></li>
<li><a class="reference internal" href="#description-of-backup-preferences" id="id14">Description of Backup Preferences</a></li>
</ul>
</li>
<li><a class="reference internal" href="#class-reference" id="id15">Class Reference</a></li>
</ul>
</div>
<div class="section" id="initializing-the-utility-class">
<h2><a class="toc-backref" href="#id1">Initializing the Utility Class</a><a class="headerlink" href="#initializing-the-utility-class" title="Permalink to this headline">¶</a></h2>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">In order to initialize the Utility class, your database
driver must already be running, since the utilities class relies on it.</p>
</div>
<p>Load the Utility Class as follows:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="p">();</span>
</pre></div>
</div>
<p>You can also pass another database object to the DB Utility loader, in case
the database you want to manage isn’t the default one:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">myutil</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">other_db</span><span class="p">,</span> <span class="k">TRUE</span><span class="p">);</span>
</pre></div>
</div>
<p>In the above example, we’re passing a custom database object as the first
parameter and then tell it to return the dbutil object, instead of
assigning it directly to <code class="docutils literal"><span class="pre">$this-&gt;dbutil</span></code>.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Both of the parameters can be used individually, just pass an empty
value as the first one if you wish to skip it.</p>
</div>
<p>Once initialized you will access the methods using the <code class="docutils literal"><span class="pre">$this-&gt;dbutil</span></code>
object:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">some_method</span><span class="p">();</span>
</pre></div>
</div>
</div>
<div class="section" id="using-the-database-utilities">
<h2><a class="toc-backref" href="#id2">Using the Database Utilities</a><a class="headerlink" href="#using-the-database-utilities" title="Permalink to this headline">¶</a></h2>
<div class="section" id="retrieve-list-of-database-names">
<h3><a class="toc-backref" href="#id3">Retrieve list of database names</a><a class="headerlink" href="#retrieve-list-of-database-names" title="Permalink to this headline">¶</a></h3>
<p>Returns an array of database names:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$dbs</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">list_databases</span><span class="p">();</span>

<span class="k">foreach</span> <span class="p">(</span><span class="nv">$dbs</span> <span class="k">as</span> <span class="nv">$db</span><span class="p">)</span>
<span class="p">{</span>
        <span class="k">echo</span> <span class="nv">$db</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
<div class="section" id="determine-if-a-database-exists">
<h3><a class="toc-backref" href="#id4">Determine If a Database Exists</a><a class="headerlink" href="#determine-if-a-database-exists" title="Permalink to this headline">¶</a></h3>
<p>Sometimes it’s helpful to know whether a particular database exists.
Returns a boolean TRUE/FALSE. Usage example:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">database_exists</span><span class="p">(</span><span class="s1">&#39;database_name&#39;</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="first admonition-title">Note</p>
<p class="last">Replace <em>database_name</em> with the name of the database you are
looking for. This method is case sensitive.</p>
</div>
</div>
<div class="section" id="optimize-a-table">
<h3><a class="toc-backref" href="#id5">Optimize a Table</a><a class="headerlink" href="#optimize-a-table" title="Permalink to this headline">¶</a></h3>
<p>Permits you to optimize a table using the table name specified in the
first parameter. Returns TRUE/FALSE based on success or failure:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">optimize_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">))</span>
<span class="p">{</span>
        <span class="k">echo</span> <span class="s1">&#39;Success!&#39;</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Not all database platforms support table optimization. It is
mostly for use with MySQL.</p>
</div>
</div>
<div class="section" id="repair-a-table">
<h3><a class="toc-backref" href="#id6">Repair a Table</a><a class="headerlink" href="#repair-a-table" title="Permalink to this headline">¶</a></h3>
<p>Permits you to repair a table using the table name specified in the
first parameter. Returns TRUE/FALSE based on success or failure:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">repair_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">))</span>
<span class="p">{</span>
        <span class="k">echo</span> <span class="s1">&#39;Success!&#39;</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Not all database platforms support table repairs.</p>
</div>
</div>
<div class="section" id="optimize-a-database">
<h3><a class="toc-backref" href="#id7">Optimize a Database</a><a class="headerlink" href="#optimize-a-database" title="Permalink to this headline">¶</a></h3>
<p>Permits you to optimize the database your DB class is currently
connected to. Returns an array containing the DB status messages or
FALSE on failure.</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$result</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">optimize_database</span><span class="p">();</span>

<span class="k">if</span> <span class="p">(</span><span class="nv">$result</span> <span class="o">!==</span> <span class="k">FALSE</span><span class="p">)</span>
<span class="p">{</span>
        <span class="nb">print_r</span><span class="p">(</span><span class="nv">$result</span><span class="p">);</span>
<span class="p">}</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Not all database platforms support database optimization. It
it is mostly for use with MySQL.</p>
</div>
</div>
<div class="section" id="export-a-query-result-as-a-csv-file">
<h3><a class="toc-backref" href="#id8">Export a Query Result as a CSV File</a><a class="headerlink" href="#export-a-query-result-as-a-csv-file" title="Permalink to this headline">¶</a></h3>
<p>Permits you to generate a CSV file from a query result. The first
parameter of the method must contain the result object from your
query. Example:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="p">();</span>

<span class="nv">$query</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">query</span><span class="p">(</span><span class="s2">&quot;SELECT * FROM mytable&quot;</span><span class="p">);</span>

<span class="k">echo</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">csv_from_result</span><span class="p">(</span><span class="nv">$query</span><span class="p">);</span>
</pre></div>
</div>
<p>The second, third, and fourth parameters allow you to set the delimiter
newline, and enclosure characters respectively. By default commas are
used as the delimiter, “n” is used as a new line, and a double-quote
is used as the enclosure. Example:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$delimiter</span> <span class="o">=</span> <span class="s2">&quot;,&quot;</span><span class="p">;</span>
<span class="nv">$newline</span> <span class="o">=</span> <span class="s2">&quot;</span><span class="se">\r\n</span><span class="s2">&quot;</span><span class="p">;</span>
<span class="nv">$enclosure</span> <span class="o">=</span> <span class="s1">&#39;&quot;&#39;</span><span class="p">;</span>

<span class="k">echo</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">csv_from_result</span><span class="p">(</span><span class="nv">$query</span><span class="p">,</span> <span class="nv">$delimiter</span><span class="p">,</span> <span class="nv">$newline</span><span class="p">,</span> <span class="nv">$enclosure</span><span class="p">);</span>
</pre></div>
</div>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">This method will NOT write the CSV file for you. It
simply creates the CSV layout. If you need to write the file
use the <a class="reference internal" href="../helpers/file_helper.html"><span class="doc">File Helper</span></a>.</p>
</div>
</div>
<div class="section" id="export-a-query-result-as-an-xml-document">
<h3><a class="toc-backref" href="#id9">Export a Query Result as an XML Document</a><a class="headerlink" href="#export-a-query-result-as-an-xml-document" title="Permalink to this headline">¶</a></h3>
<p>Permits you to generate an XML file from a query result. The first
parameter expects a query result object, the second may contain an
optional array of config parameters. Example:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="p">();</span>

<span class="nv">$query</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">query</span><span class="p">(</span><span class="s2">&quot;SELECT * FROM mytable&quot;</span><span class="p">);</span>

<span class="nv">$config</span> <span class="o">=</span> <span class="k">array</span> <span class="p">(</span>
        <span class="s1">&#39;root&#39;</span>          <span class="o">=&gt;</span> <span class="s1">&#39;root&#39;</span><span class="p">,</span>
        <span class="s1">&#39;element&#39;</span>       <span class="o">=&gt;</span> <span class="s1">&#39;element&#39;</span><span class="p">,</span>
        <span class="s1">&#39;newline&#39;</span>       <span class="o">=&gt;</span> <span class="s2">&quot;</span><span class="se">\n</span><span class="s2">&quot;</span><span class="p">,</span>
        <span class="s1">&#39;tab&#39;</span>           <span class="o">=&gt;</span> <span class="s2">&quot;</span><span class="se">\t</span><span class="s2">&quot;</span>
<span class="p">);</span>

<span class="k">echo</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">xml_from_result</span><span class="p">(</span><span class="nv">$query</span><span class="p">,</span> <span class="nv">$config</span><span class="p">);</span>
</pre></div>
</div>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">This method will NOT write the XML file for you. It
simply creates the XML layout. If you need to write the file
use the <a class="reference internal" href="../helpers/file_helper.html"><span class="doc">File Helper</span></a>.</p>
</div>
</div>
</div>
<div class="section" id="backup-your-database">
<h2><a class="toc-backref" href="#id10">Backup Your Database</a><a class="headerlink" href="#backup-your-database" title="Permalink to this headline">¶</a></h2>
<div class="section" id="database-backup-notes">
<h3><a class="toc-backref" href="#id11">Database Backup Notes</a><a class="headerlink" href="#database-backup-notes" title="Permalink to this headline">¶</a></h3>
<p>Permits you to backup your full database or individual tables. The
backup data can be compressed in either Zip or Gzip format.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">This feature is only available for MySQL and Interbase/Firebird databases.</p>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>For Interbase/Firebird databases, the backup file name is the only parameter.</p>
<p class="last">$this-&gt;dbutil-&gt;backup(‘db_backup_filename’);</p>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Due to the limited execution time and memory available to PHP,
backing up very large databases may not be possible. If your database is
very large you might need to backup directly from your SQL server via
the command line, or have your server admin do it for you if you do not
have root privileges.</p>
</div>
</div>
<div class="section" id="usage-example">
<h3><a class="toc-backref" href="#id12">Usage Example</a><a class="headerlink" href="#usage-example" title="Permalink to this headline">¶</a></h3>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="c1">// Load the DB utility class</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="p">();</span>

<span class="c1">// Backup your entire database and assign it to a variable</span>
<span class="nv">$backup</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">backup</span><span class="p">();</span>

<span class="c1">// Load the file helper and write the file to your server</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">helper</span><span class="p">(</span><span class="s1">&#39;file&#39;</span><span class="p">);</span>
<span class="nx">write_file</span><span class="p">(</span><span class="s1">&#39;/path/to/mybackup.gz&#39;</span><span class="p">,</span> <span class="nv">$backup</span><span class="p">);</span>

<span class="c1">// Load the download helper and send the file to your desktop</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">helper</span><span class="p">(</span><span class="s1">&#39;download&#39;</span><span class="p">);</span>
<span class="nx">force_download</span><span class="p">(</span><span class="s1">&#39;mybackup.gz&#39;</span><span class="p">,</span> <span class="nv">$backup</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="section" id="setting-backup-preferences">
<h3><a class="toc-backref" href="#id13">Setting Backup Preferences</a><a class="headerlink" href="#setting-backup-preferences" title="Permalink to this headline">¶</a></h3>
<p>Backup preferences are set by submitting an array of values to the first
parameter of the <code class="docutils literal"><span class="pre">backup()</span></code> method. Example:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$prefs</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;tables&#39;</span>        <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span><span class="s1">&#39;table1&#39;</span><span class="p">,</span> <span class="s1">&#39;table2&#39;</span><span class="p">),</span>   <span class="c1">// Array of tables to backup.</span>
        <span class="s1">&#39;ignore&#39;</span>        <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(),</span>                     <span class="c1">// List of tables to omit from the backup</span>
        <span class="s1">&#39;format&#39;</span>        <span class="o">=&gt;</span> <span class="s1">&#39;txt&#39;</span><span class="p">,</span>                       <span class="c1">// gzip, zip, txt</span>
        <span class="s1">&#39;filename&#39;</span>      <span class="o">=&gt;</span> <span class="s1">&#39;mybackup.sql&#39;</span><span class="p">,</span>              <span class="c1">// File name - NEEDED ONLY WITH ZIP FILES</span>
        <span class="s1">&#39;add_drop&#39;</span>      <span class="o">=&gt;</span> <span class="k">TRUE</span><span class="p">,</span>                        <span class="c1">// Whether to add DROP TABLE statements to backup file</span>
        <span class="s1">&#39;add_insert&#39;</span>    <span class="o">=&gt;</span> <span class="k">TRUE</span><span class="p">,</span>                        <span class="c1">// Whether to add INSERT data to backup file</span>
        <span class="s1">&#39;newline&#39;</span>       <span class="o">=&gt;</span> <span class="s2">&quot;</span><span class="se">\n</span><span class="s2">&quot;</span>                         <span class="c1">// Newline character used in backup file</span>
<span class="p">);</span>

<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbutil</span><span class="o">-&gt;</span><span class="na">backup</span><span class="p">(</span><span class="nv">$prefs</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="section" id="description-of-backup-preferences">
<h3><a class="toc-backref" href="#id14">Description of Backup Preferences</a><a class="headerlink" href="#description-of-backup-preferences" title="Permalink to this headline">¶</a></h3>
<table border="1" class="docutils">
<colgroup>
<col width="16%" />
<col width="16%" />
<col width="16%" />
<col width="51%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Preference</th>
<th class="head">Default Value</th>
<th class="head">Options</th>
<th class="head">Description</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><strong>tables</strong></td>
<td>empty array</td>
<td>None</td>
<td>An array of tables you want backed up. If left blank all tables will be
exported.</td>
</tr>
<tr class="row-odd"><td><strong>ignore</strong></td>
<td>empty array</td>
<td>None</td>
<td>An array of tables you want the backup routine to ignore.</td>
</tr>
<tr class="row-even"><td><strong>format</strong></td>
<td>gzip</td>
<td>gzip, zip, txt</td>
<td>The file format of the export file.</td>
</tr>
<tr class="row-odd"><td><strong>filename</strong></td>
<td>the current date/time</td>
<td>None</td>
<td>The name of the backed-up file. The name is needed only if you are using
zip compression.</td>
</tr>
<tr class="row-even"><td><strong>add_drop</strong></td>
<td>TRUE</td>
<td>TRUE/FALSE</td>
<td>Whether to include DROP TABLE statements in your SQL export file.</td>
</tr>
<tr class="row-odd"><td><strong>add_insert</strong></td>
<td>TRUE</td>
<td>TRUE/FALSE</td>
<td>Whether to include INSERT statements in your SQL export file.</td>
</tr>
<tr class="row-even"><td><strong>newline</strong></td>
<td>“\n”</td>
<td>“\n”, “\r”, “\r\n”</td>
<td>Type of newline to use in your SQL export file.</td>
</tr>
<tr class="row-odd"><td><strong>foreign_key_checks</strong></td>
<td>TRUE</td>
<td>TRUE/FALSE</td>
<td>Whether output should keep foreign key checks enabled.</td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="section" id="class-reference">
<h2><a class="toc-backref" href="#id15">Class Reference</a><a class="headerlink" href="#class-reference" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="CI_DB_utility">
<em class="property">class </em><code class="descname">CI_DB_utility</code><a class="headerlink" href="#CI_DB_utility" title="Permalink to this definition">¶</a></dt>
<dd><dl class="method">
<dt id="CI_DB_utility::backup">
<code class="descname">backup</code><span class="sig-paren">(</span><span class="optional">[</span><em>$params = array()</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::backup" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$params</strong> (<em>array</em>) – An associative array of options</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">raw/(g)zipped SQL query string</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Perform a database backup, per user preferences.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::database_exists">
<code class="descname">database_exists</code><span class="sig-paren">(</span><em>$database_name</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::database_exists" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$database_name</strong> (<em>string</em>) – Database name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE if the database exists, FALSE otherwise</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Check for the existence of a database.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::list_databases">
<code class="descname">list_databases</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::list_databases" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">Array of database names found</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">array</td>
</tr>
</tbody>
</table>
<p>Retrieve a list of all the database names.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::optimize_database">
<code class="descname">optimize_database</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::optimize_database" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">Array of optimization messages or FALSE on failure</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">array</td>
</tr>
</tbody>
</table>
<p>Optimizes the database.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::optimize_table">
<code class="descname">optimize_table</code><span class="sig-paren">(</span><em>$table_name</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::optimize_table" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table_name</strong> (<em>string</em>) – Name of the table to optimize</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Array of optimization messages or FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">array</p>
</td>
</tr>
</tbody>
</table>
<p>Optimizes a database table.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::repair_table">
<code class="descname">repair_table</code><span class="sig-paren">(</span><em>$table_name</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::repair_table" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table_name</strong> (<em>string</em>) – Name of the table to repair</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Array of repair messages or FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">array</p>
</td>
</tr>
</tbody>
</table>
<p>Repairs a database table.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::csv_from_result">
<code class="descname">csv_from_result</code><span class="sig-paren">(</span><em>$query</em><span class="optional">[</span>, <em>$delim = '</em>, <em>'</em><span class="optional">[</span>, <em>$newline = &quot;n&quot;</em><span class="optional">[</span>, <em>$enclosure = '&quot;'</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::csv_from_result" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$query</strong> (<em>object</em>) – A database result object</li>
<li><strong>$delim</strong> (<em>string</em>) – The CSV field delimiter to use</li>
<li><strong>$newline</strong> (<em>string</em>) – The newline character to use</li>
<li><strong>$enclosure</strong> (<em>string</em>) – The enclosure delimiter to use</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The generated CSV file as a string</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Translates a database result object into a CSV document.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_utility::xml_from_result">
<code class="descname">xml_from_result</code><span class="sig-paren">(</span><em>$query</em><span class="optional">[</span>, <em>$params = array()</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_utility::xml_from_result" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$query</strong> (<em>object</em>) – A database result object</li>
<li><strong>$params</strong> (<em>array</em>) – An associative array of preferences</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The generated XML document as a string</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Translates a database result object into an XML document.</p>
</dd></dl>

</dd></dl>

</div>
</div>


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