Microsoft® SQL Server® 2012 Bible

210

Part II: Building Databases and Working with Data

SELECT TRY_PARSE('Monday, 13 December 2010' AS datetime2 using

'en-US') AS Result

Result:

Result

---------------------

2010-12-13 00:00:00.0000000

The difference between the two functions is that when using the Parse function if the con-

version fails, an error is raised. However, if you use the Try_Parse function, a null value is

returned.

The last conversion introduced in SQL Server 2011 is Try_Convert(data type,

expression style). This function is the counterpart to the existing Convert function

just as the Try_Parse is to Parse. When using the Try_Convert if the conversion fails,

it returns a null value. The following script illustrates how to execute the Try_Convert

function:

SELECT TRY_CONVERT(DATE,'19720526', 112) Results

Result:

Results

-----------

1972-05-26

Server Environment Information .........................................................................

System functions return information about the current environment. This section covers

the two more commonly used system functions.

DB_NAME(): Returns the name of the current database, as shown in the following example:

SELECT CURRENT_TIMESTAMP AS [Date],

DB_NAME() AS [Database];

Result:

Date Database

------------------------- -------

2009-11-15 18:38:50.250 CHA2

SERVERPROPERTY(): Several useful pieces of information about the server may be deter-

mined from this function, including the following:

■ (^) Collation: The collation type
■ (^) Edition: Enterprise, Developer, Standard, and so on
■ (^) EngineEdition: 2 = Standard, 3 = Enterprise, 4 = Express
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