How to update only few records?

Sample code in X++ to update the few records...

Static void main updateIds(Args  args)

{

EmplTable  empltable;
 

Ttsbegin;

while select forUpdate EmplTable Index hint EmplIdIdx
                              where EmplTable.EmplId == ‘10001’;

If(emplTable.recId != 0)

{

    emplTable.EmplId = ‘10101’(New EmplId);

    EmplTable.renamePrimaryKey();

    EmplTable.update()

}

Else
{

    Info(‘employee not found’);
}

ttsCommit;

}