TRY CATCH on a CONVERT in a Select Statement

Question

Is it possible to use TRY CATCH blocks in SQL Selects?

For stuff similar to this for example:

select 
   order, 
   CONVERT(DATETIME, orderDate)
from orders

What's the best way of handling this scenario?

Answer 1

I don't know about try-catch, but in SQL Server you have the ISDATE function and can there for do something like

CASE WHEN ISDATE(orderDate) = 1 THEN CONVERT(DateTime, orderDate) ELSE GETDATE() END

Answer 2

In MS SQL Server 2012 there is a new construct that does exactly what is asked for:

SELECT 
    CASE WHEN TRY_CONVERT(float, 'test') IS NULL 
    THEN 'Cast failed'
    ELSE 'Cast succeeded'
END AS Result;
    GO

See also http://msdn.microsoft.com/en-us/library/hh230993.aspx

Answer 3

In the SELECT clause itself, no.

You can test for a date though using ISDATE()

select 
   order, 
   CASE WHEN ISDATE(orderDate) = 1 THEN CONVERT(DATETIME, orderDate) ELSE NULL END
from orders

Answer 4

I don't think a try catch is possible inside a select, but outside is possible when you're working with stored procedures.

begin try
    select cast(strartnr as int) from table
end try
begin catch 
    select 10000 from table
end catch