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Merge pull request #34446 from rwestMSFT/rw-0616-isnull
Refresh IS NOT NULL article
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‎docs/t-sql/queries/is-null-transact-sql.md‎

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title: "IS NULL (Transact-SQL)"
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description: "IS NULL (Transact-SQL)"
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description: Determines whether a specified expression is null.
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author: VanMSFT
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ms.author: vanto
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ms.date: "03/16/2017"
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ms.reviewer: randolphwest
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ms.date: 06/16/2025
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ms.service: sql
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ms.subservice: t-sql
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ms.topic: reference
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monikerRange: ">=aps-pdw-2016 || =azuresqldb-current || =azure-sqldw-latest || >=sql-server-2016 || >=sql-server-linux-2017 || =azuresqldb-mi-current || =fabric"
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---
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# IS NULL (Transact-SQL)
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[!INCLUDE [sql-asdb-asdbmi-asa-pdw-fabricse-FabricDW-FabricSQLDB](../../includes/applies-to-version/sql-asdb-asdbmi-asa-pdw-fabricse-fabricdw-fabricsqldb.md)]
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Determines whether a specified expression is NULL.
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:::image type="icon" source="../../includes/media/topic-link-icon.svg" border="false"::: [Transact-SQL syntax conventions](../../t-sql/language-elements/transact-sql-syntax-conventions-transact-sql.md)
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## Syntax
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Determines whether a specified expression is `NULL`.
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:::image type="icon" source="../../includes/media/topic-link-icon.svg" border="false"::: [Transact-SQL syntax conventions](../../t-sql/language-elements/transact-sql-syntax-conventions-transact-sql.md)
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## Syntax
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```syntaxsql
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expression IS [ NOT ] NULL
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```
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expression IS [ NOT ] NULL
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```
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## Arguments
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*expression*
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Is any valid [expression](../../t-sql/language-elements/expressions-transact-sql.md).
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NOT
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Specifies that the Boolean result be negated. The predicate reverses its return values, returning TRUE if the value is not NULL, and FALSE if the value is NULL.
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## Result Types
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**Boolean**
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## Return Code Values
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If the value of *expression* is NULL, IS NULL returns TRUE; otherwise, it returns FALSE.
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If the value of *expression* is NULL, IS NOT NULL returns FALSE; otherwise, it returns TRUE.
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## Remarks
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To determine whether an expression is NULL, use IS NULL or IS NOT NULL instead of comparison operators (such as = or !=). Comparison operators return UNKNOWN when either or both arguments are NULL.
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## Examples
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The following example returns the name and the weight for all products for which either the weight is less than `10` pounds or the color is unknown, or `NULL`.
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#### *expression*
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Any valid [expression](../language-elements/expressions-transact-sql.md).
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- `NOT`
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Specifies that the Boolean result is negated. The predicate reverses its return values, returning `TRUE` if the value isn't `NULL`, and `FALSE` if the value is `NULL`.
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## Return types
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**Boolean**
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## Return code values
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If the value of *expression* is `NULL`, `IS NULL` returns `TRUE`; otherwise, it returns `FALSE`.
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If the value of *expression* is `NULL`, `IS NOT NULL` returns `FALSE`; otherwise, it returns `TRUE`.
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## Remarks
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To determine whether an expression is `NULL`, use `IS NULL` or `IS NOT NULL` instead of comparison operators (such as `=` or `!=`). Comparison operators return `UNKNOWN` when either or both arguments are `NULL`.
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## Examples
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[!INCLUDE [article-uses-adventureworks](../../includes/article-uses-adventureworks.md)]
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### A. Return the name and weight for all products
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The following example returns the name and the weight for all products for which either the weight is less than 10 pounds, or the color is unknown, or `NULL`.
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```sql
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USE AdventureWorks2022;
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GO
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SELECT Name, Weight, Color
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FROM Production.Product
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WHERE Weight < 10.00 OR Color IS NULL
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ORDER BY Name;
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GO
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```
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## Examples: [!INCLUDE[ssazuresynapse-md](../../includes/ssazuresynapse-md.md)] and [!INCLUDE[ssPDW](../../includes/sspdw-md.md)]
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The following example returns the full names of all employees with middle initials.
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SELECT Name,
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Weight,
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Color
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FROM Production.Product
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WHERE Weight < 10.00
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OR Color IS NULL
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ORDER BY Name;
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GO
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```
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## Examples: Azure Synapse Analytics and Analytics Platform System (PDW)
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### B. Return the full names of all employees with initials
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The following example returns the full names of all employees with middle initials.
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```sql
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-- Uses AdventureWorks
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SELECT FirstName, LastName, MiddleName
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FROM DIMEmployee
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WHERE MiddleName IS NOT NULL
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ORDER BY LastName DESC;
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```
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## See Also
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[CASE &#40;Transact-SQL&#41;](../../t-sql/language-elements/case-transact-sql.md)
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[CREATE PROCEDURE &#40;Transact-SQL&#41;](../../t-sql/statements/create-procedure-transact-sql.md)
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[CREATE TABLE &#40;Transact-SQL&#41;](../../t-sql/statements/create-table-transact-sql.md)
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[Data Types &#40;Transact-SQL&#41;](../../t-sql/data-types/data-types-transact-sql.md)
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[Expressions &#40;Transact-SQL&#41;](../../t-sql/language-elements/expressions-transact-sql.md)
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[INSERT &#40;Transact-SQL&#41;](../../t-sql/statements/insert-transact-sql.md)
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[LIKE &#40;Transact-SQL&#41;](../../t-sql/language-elements/like-transact-sql.md)
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[Operators &#40;Transact-SQL&#41;](../../t-sql/language-elements/operators-transact-sql.md)
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[Logical Operators &#40;Transact-SQL&#41;](../../t-sql/language-elements/logical-operators-transact-sql.md)
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[SELECT &#40;Transact-SQL&#41;](../../t-sql/queries/select-transact-sql.md)
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[sp_help &#40;Transact-SQL&#41;](../../relational-databases/system-stored-procedures/sp-help-transact-sql.md)
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[UPDATE &#40;Transact-SQL&#41;](../../t-sql/queries/update-transact-sql.md)
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[WHERE &#40;Transact-SQL&#41;](../../t-sql/queries/where-transact-sql.md)
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SELECT FirstName,
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LastName,
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MiddleName
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FROM DIMEmployee
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WHERE MiddleName IS NOT NULL
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ORDER BY LastName DESC;
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```
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## Related content
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- [CASE (Transact-SQL)](../language-elements/case-transact-sql.md)
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- [CREATE PROCEDURE (Transact-SQL)](../statements/create-procedure-transact-sql.md)
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- [CREATE TABLE (Transact-SQL)](../statements/create-table-transact-sql.md)
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- [Data types (Transact-SQL)](../data-types/data-types-transact-sql.md)
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- [Expressions (Transact-SQL)](../language-elements/expressions-transact-sql.md)
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- [INSERT (Transact-SQL)](../statements/insert-transact-sql.md)
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- [LIKE (Transact-SQL)](../language-elements/like-transact-sql.md)
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- [Operators (Transact-SQL)](../language-elements/operators-transact-sql.md)
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- [Logical Operators (Transact-SQL)](../language-elements/logical-operators-transact-sql.md)
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- [SELECT (Transact-SQL)](select-transact-sql.md)
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- [sp_help](../../relational-databases/system-stored-procedures/sp-help-transact-sql.md)
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- [UPDATE (Transact-SQL)](update-transact-sql.md)
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- [WHERE (Transact-SQL)](where-transact-sql.md)

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