For the complete list of rules on expressions, consult Access' on-line Help. Access assumes that each extra Criteria row under the first one uses an Or operator. Access reads across each row of criteria from left to right, then starts moves down row by row. In order to combine your searches, you would need to know which items should go on the same row. The format for entering wildcards differs slightly from entering complete data.
Access inserts the Like command before the entered expression.
The following examples show various range operators. Is Null as its criteria. To select only those customers who have made purchases, use the Is Not Null statement. Creating Calculated Fields When designing fields to be included in a query, it is not limited to those in the tables and queries that the query is based on. Create new calculated fields by using expressions.