Try Catch

--example 1

BEGIN TRY

DECLARE @MyInt INT;
-- Following statement will create Devide by Zero Error
SET @MyInt = 1/0;
END TRY

BEGIN CATCH
SELECT 'Divide by zero error encountered.' ErrorMessage
END CATCH;
GO

--example 2

BEGIN TRY

DECLARE @MyInt INT;
-- Following statement will create Devide by Zero Error
SET @MyInt = 1/0;
END TRY
BEGIN CATCH
DECLARE @ErrorMessage NVARCHAR(4000);
SELECT @ErrorMessage = ERROR_MESSAGE();
RAISERROR (@ErrorMessage, 16, 1);
END CATCH;
GO

--example 3

BEGIN TRY

DECLARE @X INT
---- Divide by zero to generate Error
SET @X = 1/0
PRINT 'Command after error in TRY block'
END TRY
BEGIN CATCH
PRINT 'Error Detected'
END CATCH
PRINT 'Command after TRY/CATCH blocks'

Output:
Error Detected
Command after TRY/CATCH blocks

Merge Syntax

-- merge TABLEB with the details form table TABLEA

MERGE TABLEB                              

AS TARGET USING  

          (

                   --select querry for merge

                   SELECT

                   ColumnName1,

                   ColumnName2,

                   ColumnName3,

                   ColumnName4,

                   ColumnName5

                   FROM TABLEA

          ) as mer

ON (TARGET.ColumnName=mer.ColumnName)

WHEN MATCHED AND     

          (        TARGET.ColumnName1<>mer.ColumnName1              

                   OR TARGET.ColumnName2<>mer.ColumnName2)

THEN              

     UPDATE SET     TARGET.ColumnName1=mer.ColumnName1,             

                                                          TARGET.ColumnName2=mer.ColumnName2

WHEN NOT MATCHED BY TARGET              

THEN INSERT  

   (

                   ColumnName1,

                   ColumnName2,

                   ColumnName3,

                   ColumnName4,

                   ColumnName5 

   )  

 

VALUES

  (                mer.ColumnName1,

                   mer.ColumnName2,

                   mer.ColumnName3,

                   mer.ColumnName4,

                   mer.ColumnName5

  )