Drop view if exists

Question

I have script where I want to first drop view and then create it. I know how to drop table:

IF EXISTS (SELECT * FROM sys.tables WHERE name = 'table1' AND type = 'U') DROP TABLE table1; 

so I did the same for views:

IF EXISTS (SELECT * FROM sys.views WHERE name = 'view1' AND type = 'U') DROP VIEW view1; create view1 as(......) 

and then I got error:

'CREATE VIEW' must be the first statement in a query batch.

Answer 1

your exists syntax is wrong and you should seperate DDL with go like below

if exists(select 1 from sys.views where name='tst' and type='v') drop view tst; go  create view tst as select * from test 

you also can check existence test, with object_id like below

if object_id('tst','v') is not null drop view tst; go  create view tst as select * from test 

In SQL 2016,you can use below syntax to drop

Drop view  if exists dbo.tst 

From SQL2016 CU1,you can do below

create or alter view vwTest as  select 1 as col; go 

Answer 2

Regarding the error

'CREATE VIEW' must be the first statement in a query batch.

Microsoft SQL Server has a quirky reqirement that CREATE VIEW be the only statement in a batch. This is also true of a few other statements, such as CREATE FUNCTION. It is not true of CREATE TABLE, so go figure …

The solution is to send your script to the server in small batches. One way to do this is to select a single statement and execute it. This is clearly inconvenient.

The more convenient solution is to get the client to send the script in small isolated batches.

The GO keyword is not strictly an SQL command, which is why you can’t end it with a semicolon like real SQL commands. Instead it is an instruction to the client to break the script at this point and to send the portion as a batch.

As a result, you end up writing something like:

DROP VIEW IF EXISTS … ; GO CREATE VIEW … AS … ; GO 

None of the other database servers I have encountered (PostgreSQL, MySQL, Oracle, SQLite) have this quirk, so the requirement appears to be Microsoft Only.