![]() The second parameter's the value that you want The first's a value (usually a query field) that may contain a null value. Fortunately, there's an oddly named tool for just this task: the Nz( ) function. Instead, you want to swap those values with something more meaningful to the task at Sometimes, you don't want to specifically search for (or ignore) null values. Ignore unlinked records by reversing the condition, like so: Is Not Null ![]() Use this on the CustomerID field in the Orders table to find any orders that aren't linked to a customer. ![]() This condition matches any fields that are left blank. If you want to write a filter condition that catches null values, simply type this text into the criteria box: Is Null Values are called nulls, and you need to handle them carefully. ![]() Ordinarily, fields are optional, which means a sloppy person can leave a lot of blank values. Databases have two types of fields: required and optional.
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