We may take a
varchar input and to convert it to another data type before inserting/updating to tables. We mostly do an optimistic conversion expecting the
varchar value will be in proper convertible format. But this approach can cause exceptions when the input is not in the expected format.
In SQL Server 2012 a new function has been introduced similar to
TryParse in .NET through we can check the convertibility.
Let's say we need to check a value can be converted to
Since 4.5 is convertible to float it will return a float with value of 4.5.
In below example the value is NA and is not convertible.
The output will be
NULL in this case.
TRY_CONVERT instead of direct
CONVERT we can avoid conversion errors in the scripts.
Read http://technet.microsoft.com/en-us/library/hh230993 for details.