Cómo definir una tecla compuesta no primaria en SQL
ALTER TABLE dbo.YourTable
ADD CONSTRAINT UC_YourTable_Col1_Col2
UNIQUE(Col1, Col2)
Anxious Alligator
ALTER TABLE dbo.YourTable
ADD CONSTRAINT UC_YourTable_Col1_Col2
UNIQUE(Col1, Col2)CREATE TABLE student
(rollNumber INT,
name VARCHAR(30),
class VARCHAR(30),
section VARCHAR(1),
mobile VARCHAR(10),
PRIMARY KEY (rollNumber, mobile));CREATE TABLE student
(rollNumber INT,
name VARCHAR(30),
class VARCHAR(30),
section VARCHAR(1),
mobile VARCHAR(10),
PRIMARY KEY (rollNumber, mobile)); -- This thing