How to use 'WHERE' clause using ssp.class.php DataTables

You can use where clause like that;

$data = SSP::sql_exec( $db, $bindings,
   "SELECT SQL_CALC_FOUND_ROWS ".implode(", ", SSP::pluck($columns, 'db'))."
    FROM $table where Status = 'Unread' // <--where clause here
    $where
    $order
    $limit"
);

You should change DataTables default functions to do this!

use this ssp.class.php customized class

Link

Use it like following example:

require( 'ssp.class.php' );
$where = "Status ='Unread'";
echo json_encode(
    SSP::simple( $_GET, $sql_details, $table, $primaryKey, $columns,$where )
);

If you set $where parameter, Custom class will add where clause to select statement!

Update :

DataTables in 2015 add complex method

The new built-in method can set where clause in query!

Well.. you can't without editing or extending SSP. This is pretty bad style with alot of copied code, but SSP does not allow better customization...

class SSPCustom extends SSP
{
    /**
     *  @param  array $request Data sent to server by DataTables
     *  @param  array $sql_details SQL connection details - see sql_connect()
     *  @param  string $table SQL table to query
     *  @param  string $primaryKey Primary key of the table
     *  @param  array $columns Column information array
     *  @param  string $whereCustom Custom (additional) WHERE clause
     *  @return array          Server-side processing response array
     */
    static function simpleCustom ( $request, $sql_details, $table, $primaryKey, $columns, $whereCustom = '' )
    {
        $bindings = array();
        $db = self::sql_connect( $sql_details );

        // Build the SQL query string from the request
        $limit = self::limit( $request, $columns );
        $order = self::order( $request, $columns );
        $where = self::filter( $request, $columns, $bindings );

        if ($whereCustom) {
            if ($where) {
                $where .= ' AND ' . $whereCustom;
            } else {
                $where .= 'WHERE ' . $whereCustom;
            }
        }

        // Main query to actually get the data
        $data = self::sql_exec( $db, $bindings,
            "SELECT SQL_CALC_FOUND_ROWS `".implode("`, `", self::pluck($columns, 'db'))."`
             FROM `$table`
             $where
             $order
             $limit"
        );

        // Data set length after filtering
        $resFilterLength = self::sql_exec( $db,
            "SELECT FOUND_ROWS()"
        );
        $recordsFiltered = $resFilterLength[0][0];

        // Total data set length
        $resTotalLength = self::sql_exec( $db,
            "SELECT COUNT(`{$primaryKey}`)
             FROM   `$table`
             WHERE  " . $whereCustom
        );
        $recordsTotal = $resTotalLength[0][0];


        /*
         * Output
         */
        return array(
            "draw"            => intval( $request['draw'] ),
            "recordsTotal"    => intval( $recordsTotal ),
            "recordsFiltered" => intval( $recordsFiltered ),
            "data"            => self::data_output( $columns, $data )
        );
    }
}

Call it with:

echo json_encode(
    SSPCustom::simpleCustom( $_GET, $sql_details, $table, $primaryKey, $columns, "Status ='Unread'" )
);

Untested