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Chapter 10. Understanding Jet Operators ... > Intrinsic and Named Constants - Pg. 386

Understanding Jet Operators and Expressions 386 Tip from Use Nz to format the result sets of your crosstab queries, replacing Null values with 0. When you execute a crosstab query--such as quarterly product sales by region--cells for products with no sales in a region for the quarter are empty. Empty cells might mislead management into believing information is missing. Applying the Nz function puts a 0 in empty cells, which eliminates the ambiguity. Intrinsic and Named Constants As noted earlier in this chapter, VBA and Access have many predefined intrinsic constants. The names of these constants are considered keywords because you cannot use these names for any purpose other than returning the value represented by the names, such as -1 for True and Yes, and 0 for False and No. (True and Yes are Access synonyms, as are False and No, so you can use these pairs of values interchangeably in Access, but not in VBA.) As noted throughout the chapter, Null indicates a field without a valid entry. True, False, and Null are the most commonly used VBA intrinsic constants. T-SQL T-SQL uses 1 for TRUE and 0 for FALSE. Conversion between -1 for True and 1 for TRUE succeeds because True accepts any non-0 number as Not False. The Upsizing Wizard converts Jet Boolean fields to the SQL Server bit data type.