Use correct Boolean to reverse a logical AND

If you have a Boolean condition combining two clauses with AND, remember your Boolean algebra if you want to negate the statement.

Remember to change not only the operator in the individual condition but also the linking “AND” to an “OR.”

For example, selecting your high priority products is:

{@ProductType} = “Top” AND {@Sales} > 5000

The opposite, to select your low priority products is:

{@ProductType} <> “Top” OR {@Sales} <= 5000

Use Boolean parameters

The report has a Boolean field to indicate if the Customer was active (or not). Our user wanted the report to select Active or Inactive clients.

We used a Boolean parameter, and then to make it the question easier to answer, we created a default pick list with True and False and a description against each one. Then the selection formula was a simple

{Customer.Active} = {?Active}

Use IMP in your Boolean formulas to find many True values

The Imp operator returns TRUE if the two values agree, or the second value is true.

True IMP True returns True
True IMP False returns False
False IMP True returns True
False IMP False returns True

Unlike all the other Boolean operators, this is not a symmetrical operator. The order of the two Boolean values either side of the IMP does matter.

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