[Stinged]

You should select the player's password in that query when they connect.
And then when you check if the row exists (You've already done that), load it using

Код:

cache_get_field_content(0, "Password", PlayerInfo[playerid][Password], size here);

You can even use field indexes instead (cache_get_row). It's faster than using field names.
But they depend on how you select the password when they connect.