Filtering empty or null values
Sometimes report columns have blank data rows. Consider a customer database that contains an e-mail field. For customers who did not supply an e-mail address, the e-mail field in the column is empty or blank. An empty value, also called a null value, means that no value is available. Null values apply to all data types.
You can create a filter to exclude data rows when a specific column has null values. When filtering to exclude rows containing null values, use the Is Not Null operator. If you want to only view rows with null values in a particular column, use the Is Null operator. For example, the following filter condition excludes customer data where the e-mail column contains null values:
Email Is Not Null
The following filter condition displays only rows where the e-mail column contains null values:
Email Is Null

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