Moving, initializing or setting uninitialized data
to initialize a table or data item when you suspect that a problem
might be caused by residual data in those fields.
If the problem happens intermittently and not always
with the same data, it could be that a switch was not initialized
but is generally set to the right value (0 or 1) by chance. By using
SET statement to ensure that the switch is initialized,
you can determine that the uninitialized switch is the cause of the
problem or remove it as a possible cause.