I have some SQL code that needs to be executed if a certain View exists in a database. How would I go about checking if the View exists?
EDIT: The DBMS being used is Mic
This is the most portable, least intrusive way:
select
count(*)
from
INFORMATION_SCHEMA.VIEWS
where
table_name = 'MyView'
and table_schema = 'MySchema'
Edit: This does work on SQL Server, and it doesn't require you joining to sys.schemas to get the schema of the view. This is less important if everything is dbo, but if you're making good use of schemas, then you should keep that in mind.
Each RDBMS has their own little way of checking metadata like this, but information_schema is actually ANSI, and I think Oracle and apparently SQLite are the only ones that don't support it in some fashion.
if exists (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[MyTable]') )
You can check the availability of the view in various ways
FOR SQL SERVER
use sys.objects
IF EXISTS(
SELECT 1
FROM sys.objects
WHERE OBJECT_ID = OBJECT_ID('[schemaName].[ViewName]')
AND Type_Desc = 'VIEW'
)
BEGIN
PRINT 'View Exists'
END
use sysobjects
IF NOT EXISTS (
SELECT 1
FROM sysobjects
WHERE NAME = '[schemaName].[ViewName]'
AND xtype = 'V'
)
BEGIN
PRINT 'View Exists'
END
use sys.views
IF EXISTS (
SELECT 1
FROM sys.views
WHERE OBJECT_ID = OBJECT_ID(N'[schemaName].[ViewName]')
)
BEGIN
PRINT 'View Exists'
END
use INFORMATION_SCHEMA.VIEWS
IF EXISTS (
SELECT 1
FROM INFORMATION_SCHEMA.VIEWS
WHERE table_name = 'ViewName'
AND table_schema = 'schemaName'
)
BEGIN
PRINT 'View Exists'
END
use OBJECT_ID
IF EXISTS(
SELECT OBJECT_ID('ViewName', 'V')
)
BEGIN
PRINT 'View Exists'
END
use sys.sql_modules
IF EXISTS (
SELECT 1
FROM sys.sql_modules
WHERE OBJECT_ID = OBJECT_ID('[schemaName].[ViewName]')
)
BEGIN
PRINT 'View Exists'
END
IN SQL Server ,
declare @ViewName nvarchar(20)='ViewNameExample'
if exists(SELECT 1 from sys.objects where object_Id=object_Id(@ViewName) and Type_Desc='VIEW')
begin
-- Your SQL Code goes here ...
end