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TRY_PARSE (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Returns the result of an expression, translated to the requested data type, or null if the cast fails in SQL Server. Use TRY_PARSE only for converting from string to date/time and number types.

Transact-SQL syntax conventions

Syntax

TRY_PARSE ( string_value AS data_type [ USING culture ] )  

Arguments

string_value
nvarchar(4000) value representing the formatted value to parse into the specified data type.

string_value must be a valid representation of the requested data type, or TRY_PARSE returns null.

data_type
Literal representing the data type requested for the result.

culture
Optional string that identifies the culture in which string_value is formatted.

If the culture argument is not provided, the language of the current session is used. This language is set either implicitly or explicitly by using the SET LANGUAGE statement. culture accepts any culture supported by the .NET Framework; it is not limited to the languages explicitly supported by SQL Server. If the culture argument is not valid, PARSE raises an error.

Return Types

Returns the result of the expression, translated to the requested data type, or null if the cast fails.

Remarks

Use TRY_PARSE only for converting from string to date/time and number types. For general type conversions, continue to use CAST or CONVERT. Keep in mind that there is a certain performance overhead in parsing the string value.

TRY_PARSE relies on the presence of .the .NET Framework Common Language Runtime (CLR).

This function will not be remoted since it depends on the presence of the CLR. Remoting a function that requires the CLR would cause an error on the remote server.

More information about the data_type parameter

The values for the data_type parameter are restricted to the types shown in the following table, together with styles. The style information is provided to help determine what types of patterns are allowed. For more information on styles, see the .NET Framework documentation for the System.Globalization.NumberStyles and DateTimeStyles enumerations.

Category Type .NET type Styles used
Numeric bigint Int64 NumberStyles.Number
Numeric int Int32 NumberStyles.Number
Numeric smallint Int16 NumberStyles.Number
Numeric tinyint Byte NumberStyles.Number
Numeric decimal Decimal NumberStyles.Number
Numeric numeric Decimal NumberStyles.Number
Numeric float Double NumberStyles.Float
Numeric real Single NumberStyles.Float
Numeric smallmoney Decimal NumberStyles.Currency
Numeric money Decimal NumberStyles.Currency
Date and Time date DateTime DateTimeStyles.AllowWhiteSpaces | DateTimeStyles.AssumeUniversal
Date and Time time TimeSpan DateTimeStyles.AllowWhiteSpaces | DateTimeStyles.AssumeUniversal
Date and Time datetime DateTime DateTimeStyles.AllowWhiteSpaces | DateTimeStyles.AssumeUniversal
Date and Time smalldatetime DateTime DateTimeStyles.AllowWhiteSpaces | DateTimeStyles.AssumeUniversal
Date and Time datetime2 DateTime DateTimeStyles.AllowWhiteSpaces | DateTimeStyles.AssumeUniversal
Date and Time datetimeoffset DateTimeOffset DateTimeStyles.AllowWhiteSpaces | DateTimeStyles.AssumeUniversal

More information about the culture parameter

The following table shows the mappings from SQL Server languages to .NET Framework cultures.

Full name Alias LCID Specific culture
us_english English 1033 en-US
Deutsch German 1031 de-DE
Français French 1036 fr-FR
日本語 Japanese 1041 ja-JP
Dansk Danish 1030 da-DK
Español Spanish 3082 es-ES
Italiano Italian 1040 it-IT
Nederlands Dutch 1043 nl-NL
Norsk Norwegian 2068 nn-NO
Português Portuguese 2070 pt-PT
Suomi Finnish 1035 fi-FI
Svenska Swedish 1053 sv-SE
čeština Czech 1029 Cs-CZ
magyar Hungarian 1038 Hu-HU
polski Polish 1045 Pl-PL
română Romanian 1048 Ro-RO
hrvatski Croatian 1050 hr-HR
slovenčina Slovak 1051 Sk-SK
slovenski Slovenian 1060 Sl-SI
ελληνικά Greek 1032 El-GR
български Bulgarian 1026 bg-BG
русский Russian 1049 Ru-RU
Türkçe Turkish 1055 Tr-TR
British British English 2057 en-GB
eesti Estonian 1061 Et-EE
latviešu Latvian 1062 lv-LV
lietuvių Lithuanian 1063 lt-LT
Português (Brasil) Brazilian 1046 pt-BR
繁體中文 Traditional Chinese 1028 zh-TW
한국어 Korean 1042 Ko-KR
简体中文 Simplified Chinese 2052 zh-CN
Arabic Arabic 1025 ar-SA
ไทย Thai 1054 Th-TH

Examples

A. Simple example of TRY_PARSE

SELECT TRY_PARSE('Jabberwokkie' AS datetime2 USING 'en-US') AS Result;  

Here's the result set.

Result  
---------------  
NULL  
  
(1 row(s) affected)  

B. Detecting nulls with TRY_PARSE

SELECT  
    CASE WHEN TRY_PARSE('Aragorn' AS decimal USING 'sr-Latn-CS') IS NULL  
        THEN 'True'  
        ELSE 'False'  
END  
AS Result;  

Here's the result set.

Result  
---------------  
True  
  
(1 row(s) affected)  

C. Using IIF with TRY_PARSE and implicit culture setting

SET LANGUAGE English;  
SELECT IIF(TRY_PARSE('01/01/2011' AS datetime2) IS NULL, 'True', 'False') AS Result;

Here's the result set.

Result  
---------------  
False  
  
(1 row(s) affected)  

See Also

PARSE (Transact-SQL)
Conversion Functions (Transact-SQL)
TRY_CONVERT (Transact-SQL)
CAST and CONVERT (Transact-SQL)