This post show code for execute/run query for Direct MySQL query for create, read, update and delete.

Method 1

// database Connection for read query
$core_read = Mage::getSingleton('core/resource')->getConnection('core_read');  
// database Connection for write query 
$core_write = Mage::getSingleton('core/resource')->getConnection('core_write');
 
// read and write function for query
$read_methods = get_class_methods(get_class($core_read));
foreach($read_methods as $value)
{
	echo $value."\n"; // echo value
}
$write_methods = get_class_methods(get_class($core_write));
foreach($write_methods as $r)
{
	echo $value."\n"; // echo value 
}

Read Query and returns as array In Magento.

$query_results = $core_read->fetchAll("select * from your_table_name where your_column_name like '%some_data'"); 
var_dump($query_results[0]);
foreach($query_results as $value)
{
    var_dump($value); // print result
}


Insert Query For Magento.

$core_write->insert(
        "your_table_name", 
        array("your_column_name" => column_value, "your_column_name" => column_value ));
		// add your column name and value

Update Query For Magento.

$core_write->update(
        "your_table_name",
        array("your_column_name" => column_values, "your_column_name" => column_values ),
        "entity_id=116");
		// add your column name, value and entity_id


Delete Query For Magento.

$core_write->delete(
    "your_table_name",
    "entity_id=116"
);


Magento Query for create, read, update, and delete operations.

$query_results = $core_read->query("select * from your_table_name");
var_dump($query_results);
foreach($query_results as $value)
{
    var_dump($value); // print result
}

Method 2

Magento : Create Database Connections

// database Connection for read query
$core_read = Mage::getSingleton('core/resource')->getConnection('core_read'); 
// database Connection for write query 
$core_write = Mage::getSingleton('core/resource')->getConnection('core_write'); 


Magento : Custom Insert Query

// database Connection for write query 
$connection = Mage::getSingleton('core/resource')->getConnection('core_write');
// Custom insert query in Magento
$sql = &quot;INSERT INTO <code>your_table_name</code> (<code>YOUR_COLUMN_NAME</code>,<code>YOUR_COLUMN_NAME</code>,<code>YOUR_COLUMN_NAME</code>) VALUES ('116','TEST','Test this query')&quot;;
$connection-&gt;query($sql);


&lt;strong&gt;Magento : Custom Select Query&lt;/strong&gt;


// database Connection for read query
$core_read = Mage::getSingleton('core/resource')-&gt;getConnection('core_read');
// add your table name
$query_value = $core_read-&gt;query(&quot;select * from your_table_name&quot;);
while ($rows = $query_value-&gt;fetch()) // fetch value 
{
	// print result of query
	print_r($rows); 
};

Magento : Custom Truncate a Table Query

// database Connection for read query
$core_read = Mage::getSingleton('core/resource')->getConnection('core_read');
// Truncate Table
$core_read->query("truncate table your_table_name"); // add your table name

Magento : Custom Update Query

$data = array("YOUR_COLUMN_NAME" => "column_value", "YOUR_COLUMN_NAME" => "column_value");
$where_condition = " id = 116 "; // add your where condition
$core_write->update("TABLE_NAME", $data, $where_condition);
// database Connection for write query 
$core_write = Mage::getSingleton('core/resource')->getConnection('core_write');
$core_write->query("update your_table_name set YOUR_COLUMN_NAME = 'column_value'");

Magento : Custom Delete Query

$where_condition = " id = 116 "; // add your where condition
// database Connection for write query 
$core_write = Mage::getSingleton('core/resource')->getConnection('core_write');
$core_write->delete("your_table_name", $where_condition); // Or Try this
$core_write->query("delete from your_table_name where YOUR_COLUMN_NAME = 'column_value'");