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Merge pull request #33663 from rwestMSFT/rw-0331-fix-10049
Clarifying Transact-SQL ROUND behavior (PR 10049)
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‎docs/t-sql/functions/round-transact-sql.md

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---
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title: "ROUND (Transact-SQL)"
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description: "ROUND (Transact-SQL)"
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description: ROUND returns a numeric value, rounded to the specified length or precision.
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author: MikeRayMSFT
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ms.author: mikeray
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ms.date: "12/14/2017"
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ms.reviewer: randolphwest
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ms.date: 03/31/2025
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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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- "ROUND function [Transact-SQL]"
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dev_langs:
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- "TSQL"
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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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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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# ROUND (Transact-SQL)
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[!INCLUDE [sql-asdb-asdbmi-asa-pdw-fabricse-fabricdw](../../includes/applies-to-version/sql-asdb-asdbmi-asa-pdw-fabricse-fabricdw.md)]
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Returns a numeric value, rounded to the specified length or precision.
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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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Returns a numeric value, rounded to the specified length or precision.
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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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ROUND ( numeric_expression , length [ ,function ] )
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```
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ROUND ( numeric_expression , length [ , function ] )
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```
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## Arguments
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*numeric_expression*
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Is an [expression](../../t-sql/language-elements/expressions-transact-sql.md) of the exact numeric or approximate numeric data type category.
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*length*
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Is the precision to which *numeric_expression* is to be rounded. *length* must be an expression of type **tinyint**, **smallint**, or **int**. When *length* is a positive number, *numeric_expression* is rounded to the number of decimal positions specified by *length*. When *length* is a negative number, *numeric_expression* is rounded on the left side of the decimal point, as specified by *length*.
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*function*
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Is the type of operation to perform. *function* must be **tinyint**, **smallint**, or **int**. When *function* is omitted or has a value of 0 (default), *numeric_expression* is rounded. When a value other than 0 is specified, *numeric_expression* is truncated.
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## Return Types
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Returns the following data types.
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|Expression result|Return type|
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|-----------------------|-----------------|
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|**tinyint**|**int**|
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|**smallint**|**int**|
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|**int**|**int**|
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|**bigint**|**bigint**|
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|**decimal** and **numeric** category (p, s)|**decimal(p, s)**|
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|**money** and **smallmoney** category|**money**|
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|**float** and **real** category|**float**|
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## Remarks
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ROUND always returns a value. If *length* is negative and larger than the number of digits before the decimal point, ROUND returns 0.
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|Example|Result|
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|-------------|------------|
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|ROUND(748.58, -4)|0|
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ROUND returns a rounded *numeric_expression*, regardless of data type, when *length* is a negative number.
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|Examples|Result|
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|--------------|------------|
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|ROUND(748.58, -1)|750.00|
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|ROUND(748.58, -2)|700.00|
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|ROUND(748.58, -3)|Results in an arithmetic overflow, because 748.58 defaults to decimal(5,2), which cannot return 1000.00.|
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|To round up to 4 digits, change the data type of the input. For example:<br /><br /> `SELECT ROUND(CAST (748.58 AS decimal (6,2)),-3);`|1000.00|
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## Examples
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### A. Using ROUND and estimates
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The following example shows two expressions that demonstrate by using `ROUND` the last digit is always an estimate.
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```sql
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SELECT ROUND(123.9994, 3), ROUND(123.9995, 3);
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GO
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```
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[!INCLUDE[ssResult](../../includes/ssresult-md.md)]
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```
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----------- -----------
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123.9990 124.0000
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```
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### B. Using ROUND and rounding approximations
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The following example shows rounding and approximations.
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```
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SELECT ROUND(123.4545, 2), ROUND(123.45, -2);
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```
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[!INCLUDE[ssResult](../../includes/ssresult-md.md)]
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```
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#### *numeric_expression*
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An [expression](../../t-sql/language-elements/expressions-transact-sql.md) of the exact numeric or approximate numeric data type category.
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#### *length*
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The precision to which *numeric_expression* is to be rounded. *length* must be an expression of type **tinyint**, **smallint**, or **int**. When *length* is a positive number, *numeric_expression* is rounded to the number of decimal positions specified by *length*. When *length* is a negative number, *numeric_expression* is rounded on the left side of the decimal point, as specified by *length*.
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#### *function*
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The type of operation to perform. *function* must be **tinyint**, **smallint**, or **int**. When *function* is omitted or has a value of `0` (default), *numeric_expression* is rounded. When a value other than `0` is specified, *numeric_expression* is truncated.
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## Return types
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Returns the following data types.
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| Expression result | Return type |
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| --- | --- |
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| **tinyint** | **int** |
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| **smallint** | **int** |
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| **int** | **int** |
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| **bigint** | **bigint** |
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| **decimal** and **numeric** category (p, s) | **decimal(p, s)** |
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| **money** and **smallmoney** category | **money** |
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| **float** and **real** category | **float** |
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## Remarks
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- `ROUND` always returns a value. If *length* is negative and larger than the number of digits before the decimal point, `ROUND` returns `0`.
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| Example | Result |
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| --- | --- |
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| `ROUND(748.58, -4)` | 0 |
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- `ROUND` returns a rounded *numeric_expression*, regardless of data type, when *length* is a negative number.
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| Examples | Result |
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| --- | --- |
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| `ROUND(748.58, -1)` | 750.00 |
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| `ROUND(748.58, -2)` | 700.00 |
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| `ROUND(748.58, -3)` | Results in an arithmetic overflow, because 748.58 defaults to **decimal(5, 2)**, which can't return `1000.00`. |
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- To round up to four digits, change the data type of the input. For example:
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```sql
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SELECT ROUND(CAST (748.58 AS DECIMAL (6, 2)), -3);
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```
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[!INCLUDE [ssresult-md](../../includes/ssresult-md.md)]
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```output
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1000.00
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```
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- `ROUND` breaks ties by rounding half away from zero (also known as commercial rounding).
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| Examples | Result |
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| --- | --- |
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| `ROUND(1.15, 1)` | 1.2 |
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| `ROUND(-1.15, 1)` | -1.2 |
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## Examples
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### A. Use ROUND and estimates
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The following example shows two expressions that demonstrate by using `ROUND`, the last digit is always an estimate.
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```sql
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SELECT ROUND(123.9994, 3),
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ROUND(123.9995, 3);
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GO
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```
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[!INCLUDE [ssresult-md](../../includes/ssresult-md.md)]
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```output
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----------- -----------
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123.9990 124.0000
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```
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### B. Use ROUND and rounding approximations
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The following example shows rounding and approximations.
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```sql
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SELECT ROUND(123.4545, 2),
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ROUND(123.45, -2);
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```
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[!INCLUDE [ssresult-md](../../includes/ssresult-md.md)]
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```output
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---------- ----------
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123.4500 100.00
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```
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### C. Using ROUND to truncate
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The following example uses two `SELECT` statements to demonstrate the difference between rounding and truncation. The first statement rounds the result. The second statement truncates the result.
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```sql
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SELECT ROUND(150.75, 0);
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GO
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SELECT ROUND(150.75, 0, 1);
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GO
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```
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[!INCLUDE[ssResult](../../includes/ssresult-md.md)]
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```
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--------
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151.00
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(1 row(s) affected)
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--------
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150.00
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(1 row(s) affected)
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### C. Use ROUND to truncate
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The following example uses two `SELECT` statements to demonstrate the difference between rounding and truncation. The first statement rounds the result. The second statement truncates the result.
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```sql
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SELECT ROUND(150.75, 0);
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GO
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```
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## See Also
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[CEILING &#40;Transact-SQL&#41;](../../t-sql/functions/ceiling-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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[FLOOR &#40;Transact-SQL&#41;](../../t-sql/functions/floor-transact-sql.md)
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[Mathematical Functions &#40;Transact-SQL&#41;](../../t-sql/functions/mathematical-functions-transact-sql.md)
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[!INCLUDE [ssresult-md](../../includes/ssresult-md.md)]
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```output
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151.00
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```
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```sql
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SELECT ROUND(150.75, 0, 1);
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GO
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```
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[!INCLUDE [ssresult-md](../../includes/ssresult-md.md)]
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```output
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150.00
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```
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## Related content
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- [CEILING (Transact-SQL)](ceiling-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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- [FLOOR (Transact-SQL)](floor-transact-sql.md)
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- [Mathematical functions (Transact-SQL)](mathematical-functions-transact-sql.md)

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