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Integrity Constraints in Create Table not null primary key (A1,...A) foreign key (Am,...An)references r Example: create table instructor ID char(5), name varchar(20)not null, dept name varchar(20), salary numeric(8,2), primary key (ID), foreign key(dept_name)references department), primary key declaration on an attribute automatically ensures not null Database System Concepts-6th Edition 3.7 @Silberschatz,Korth and SudarshanDatabase System Concepts - 6 3.7 ©Silberschatz, Korth and Sudarshan th Edition Integrity Constraints in Create Table not null primary key (A1 , ..., An ) foreign key (Am, ..., An ) references r Example: create table instructor ( ID char(5), name varchar(20) not null, dept_name varchar(20), salary numeric(8,2), primary key (ID), foreign key (dept_name) references department); primary key declaration on an attribute automatically ensures not null
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