Optimalizace příkazu v PHP + mysql

Tabulka "data"
------------------------------
id (AI, PK)
name 
url
table
..


tabulka data_images
------------------------------
id (AI, PK)
data_id (z tabulky "data.id")
directory


tabulka g_123, g_755
----------------
id,
data_id,
text,
info,
a
b
...

public function data() {
            
            $i=0;
            
            $this->getObjects   = "";
            $start              = 0;
            $max                = 30;

            $this->data_cmd  = "
                            SELECT object.*, timg.dir AS images FROM data object
                                LEFT JOIN data_images timg ON timg.data_id = object.id
                                    WHERE object.sv_block=0
                                        ORDER BY object.created 
                                            DESC LIMIT $start, $max";  
 

            $this->qPar = mysqli_query( $this->data_cmd );
            while($this->gObj = mysqli_fetch_array($this->qPar)) {

                $this->getObjects[$i] = array(
                    
                    "id" => $this->gObj["id"],      
                    "ab" => $this->gObj["ab"],
                    "name" => $this->gObj["name"],
                    "data" => DCMD("SELECT * FROM {$this->gObj["table"]} WHERE data_id='".$this->gObj["id"]."' ;"),
                    "images" =>  $this->gObj["images"],
                    "created" => $this->gObj["created"],       
                );

                $i++;
                
            }
            
            return $this->getObjects;
            
            
}