MFrSUQSc

1DELETE FROM TableName;
2
3DELETE FROM TableName WHERE <where-condition>;
4
5-- Using Sub query
6DELETE FROM dbo.Table1 T1
7WHERE EXISTS (SELECT 1 
8        FROM Table2 T2
9        WHERE T1.Col1 = T2.Col1)
10 
11-- Using a Join
12DELETE Supplier
13   FROM Supplier
14   JOIN Contact
15	 ON Supplier.ContactID = Contact.ContactID
16	 WHERE Contact.FirstName= 'Terri';
17   
18
19-- Building a foreign key with referential integrity
20-- that cascades deletes
21
22-- SAMPLE MAPPING TABLE
23CREATE TABLE dbo.BlackListedSuppliers (
24   BlackListedSupplierID INT IDENTITY NOT NULL
25            PRIMARY KEY NONCLUSTERED,
26   SupplierID UNIQUEIDENTIFIER NOT NULL
27    FOREIGN KEY REFERENCES dbo.Supplier 
28            ON DELETE CASCADE,
29   CONTACTID  UNIQUEIDENTIFIER NOT NULL
30    FOREIGN KEY REFERENCES dbo.Contact
31            ON DELETE CASCADE,
32)
33 ON [PRIMARY]
34
35-- NOW IF A PRIMARY ROW IS DELETED FROM 
36-- THE MAIN TABLE > SUPPLIER, THE FOREIGN KEY
37-- WILL ALSO DELETE THE SECONDARY ROW IN 
38-- THE SECONDARY TABLE