What is a NULL Value? A field with a NULL value is a field with no value. If a field in a table is optional, it is possible to insert a new record or update a record without adding a value to this …

Mar 6, 2012 · SQL provides the special syntax for testing if a column is null, via is null and is not null, which is a special condition to test for a null (or not a null). Here's some SQL showing a …

Dec 23, 2024 · NULL values in SQL are essential for representing missing or inapplicable data. Understanding their behavior, impact on constraints, and three-valued logic is crucial for …

May 19, 2021 · This article will explain what problems can occur when working with SQL NULL values and it also gives some solution recommendations to overcome these issues. What is a …

May 18, 2011 · On MS SQL Server, the ISNULL() function returns the first argument if it's not NULL, otherwise it returns the second. You can effectively use this to make sure a query …

In SQL, null or NULL is a special marker used to indicate that a data value does not exist in the database. Introduced by the creator of the relational database model, E. F. Codd , SQL null …

Dec 4, 2009 · The expression "NULL = NULL" evaluates to NULL, but is actually invalid in SQL; yet ORDER BY treats NULLs as equal (whatever they precede or follow "regular" values is left …

Mar 17, 2021 · NULL is a special value in SQL that represents a missing or an unknown value. NULL is used for fields with unknown or inapplicable values. It's different from an empty or …

Jun 20, 2024 · This tip will help you understand what NULL means in the context of the Microsoft Fabric data universe, which includes SQL Server. It will then show how these values can make …

Feb 24, 2025 · NULL in SQL: Learn to manage missing data with IS NULL, IS NOT NULL, COALESCE, and NULLIF functions for robust database queries.