Question

I am creating a class (Datamap) that will help me simplify my queries in my model class. Basically, this class (Datamap) is use in conjunction with my db class.

Previously for an insert statement in my model I need.

$db->query("INSERT INTO test(id,name) VALUES("id","name")");

Now, with the Datamap class, it will be like

$datamap->create("test","id=id&name=name");

Below is snippet code from the Datamap class that I created.

    function create($tablename,$variables){
    $id=0;
    $tbl = $this->creturnval($variables);
    $tblVal = $tbl[0];
    $tblData = $tbl[1];
    $this->db->execute("INSERT into $tablename($tblVal) VALUES($tblData);");
    $id = $this->db->lastInsertedId();
    return $id;
}


function creturnval($variables){
    $vars = explode("&",$variables);
    $count = sizeOf($vars);
    $tblVal = "";
    $tblData = "";
    for($i=0;$i<$count;$i++){
        $d = explode("=",$vars[$i]);
        $tblVal.= $d[0].",";
        $tblData.= "'".$d[1]."'".",";
    }
    $tblVal = rtrim($tblVal, ',');
    $tblData = rtrim($tblData, ',');
    $return[0] = $tblVal;
    $return[1] = $tblData;
    return $return;
}

My concern is actually the performance issue. Previously in my model class, if I just used $db->query(), it seems to be faster because I do not have to go through 2 functions.

Now, in order to do an insert, I will need to parse the variables, split & etc, then process it.

My idea of using this Datamap class is actually to provide more maintainability and standardization. This is to prevent all my model classes from having sql statements over the place which looks untidy.

Do you think this will pose a possible performance issue?

PS: I am using my own framework that I build for my web application

Appreciate all advice.

Answer 1

I think a more common way of writting SQL wrappers is like this:

$item = $datamap->create("test");
$item->setValue("id", $id);
$item->setvalue("name", $name);
$item->update(); // push to database

$datamap->create(); return an object that will hold the values for a record. setValue and getValue allow you to access it. update pushes new values to the database. Similarly, you could implement $datamap->get("test", 1234); where 1234 is the id of the record you want to fetch. get returns the same object as create, with the same functions. update will then cause an UPDATE instead of an INSERT. After inserting a record using update you can use mysql_last_insert_id() to fetch the id and set it in the object so you can perform UPDATEs on it after that point. (The object has to keep track of it’s ‘state’).