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    <p>There are some libraries, such as MDB2 in PEAR that make querying a bit easier and safer.</p> <p>Unfortunately, they can be a bit wordy to set up, and you sometimes have to pass them the same info twice. I've used MDB2 in a couple of projects, and I tended to write a thin veneer around it, especially for specifying the types of fields. I generally make an object that knows about a particular table and its columns, and then a helper function in that fills in field types for me when I call an MDB2 query function.</p> <p>For instance:</p> <pre><code>function MakeTableTypes($TableName, $FieldNames) { $Types = array(); foreach ($FieldNames as $FieldName =&gt; $FieldValue) { $Types[] = $this-&gt;Tables[$TableName]['schema'][$FieldName]['type']; } return $Types; } </code></pre> <p>Obviously this object has a map of table names -> schemas that it knows about, and just extracts the types of the fields you specify, and returns an matching type array suitable for use with an MDB2 query.</p> <p>MDB2 (and similar libraries) then handle the parameter substitution for you, so for update/insert queries, you just build a hash/map from column name to value, and use the 'autoExecute' functions to build and execute the relevant query.</p> <p>For example:</p> <pre><code>function UpdateArticle($Article) { $Types = $this-&gt;MakeTableTypes($table_name, $Article); $res = $this-&gt;MDB2-&gt;extended-&gt;autoExecute($table_name, $Article, MDB2_AUTOQUERY_UPDATE, 'id = '.$this-&gt;MDB2-&gt;quote($Article['id'], 'integer'), $Types); } </code></pre> <p>and MDB2 will build the query, escaping everything properly, etc.</p> <p>I'd recommend measuring performance with MDB2 though, as it pulls in a fair bit of code that might cause you problems if you're not running a PHP accelerator.</p> <p>As I say, the setup overhead seems daunting at first, but once it's done the queries can be simpler/more symbolic to write and (especially) modify. I think MDB2 should know a bit more about your schema, which would simpify some of the commonly used API calls, but you can reduce the annoyance of this by encapsulating the schema yourself, as I mentioned above, and providing simple accessor functions that generate the arrays MDB2 needs to perform these queries.</p> <p>Of course you can just do flat SQL queries as a string using the query() function if you want, so you're not forced to switch over to the full 'MDB2 way' - you can try it out piecemeal, and see if you hate it or not.</p>
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