In this section, you will explore enhancements in Data Manipulation Language (DML) and Data Definition Language (DDL) that are not part of new features or improved features from previous SQL Server versions.
The section starts with a small syntax extension that you will use often in the code examples in this book.
With a conditionalDROP statement, you can avoid getting an exception if the object you want to drop does not exist. If, for instance, the T1 table has already been removed or it was not created at all, the following statement will fail:
DROP TABLE dbo.T1;
Here is the error message:
Msg 3701, Level 11, State 5, Line 5Cannot drop the table 'dbo.T1', because it does not exist or you do not have permission.
SQL Server 2016 introduces the conditional DROP statement for most of the database objects. The conditional DROP statement is a DROP statement extended with the IF EXISTS part. Repeat the preceding command...