Just wanted to point out that OR combines two conditions. As far as I know; it means that 'Expression A' and 'Expression B' are evaluated and then the OR operator is applied for evaluating the final result of the 'Expression A OR B'.

So,

IF A OR B

BEGIN

{do something}

END

is not the same as

IF A

BEGIN

{do something}

END

IF B

BEGIN

{do something}

END