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