Diffrence between query_read and query_write?

[alqassam]

Hello,
I want to know the diffrence between "query_read" and "query_write" commands??

I know i should use "query_read" for ("SELECT","SHOW") and "query_write" for ("INSERT","UPDATE","DELETE","REPLACE",... etc)

But when i revised the file "class_core.php" i found:

PHP Code:

function query_read($sql, $buffered = true)
    {
        $this->sql =& $sql;
        return $this->execute_query($buffered, $this->connection_master);
    } 


PHP Code:

function query_write($sql, $buffered = true)
    {
        $this->sql =& $sql;
        return $this->execute_query($buffered, $this->connection_master);
    } 


The same thing !!
what's the diffrence between them ? and can i use "query_read" for write queries and "query_write" for read queries?