DBMS Unit II: Relation Schema and Properties

The CHECK constraint in the student table ensures that the age of a student is greater than 18.

The error message displayed is CHECK constraint failed: age>18.

Each entity in the ER model becomes a table, and all attributes of the entity become columns of the table. The key attribute of the entity becomes the primary key of the table.

<p>Each relationship in the ER model becomes a table, and the key attributes of the participating entities in the relationship become the columns of the table. If the relationship has any attributes, they also become columns of the table.</p> Signup and view all the answers

<p>The <code>PRIMARY KEY</code> constraint ensures that the <code>EmpID</code> column in the <code>Employee</code> table and the <code>DeptID</code> column in the <code>Department</code> table uniquely identify each row in the respective tables.</p> Signup and view all the answers

<p>The <code>INSERT INTO</code> statement is used to add new rows of data to the <code>student</code> table.</p> Signup and view all the answers

<p>The <code>SELECT * FROM</code> statement is used to retrieve all the rows and columns from the <code>student</code> table.</p> Signup and view all the answers

<p>The <code>CHECK</code> constraint in the <code>student</code> table ensures that the <code>age</code> of a student is greater than 18.</p> Signup and view all the answers

<p>The <code>DBMS UNIT II LOGICAL DATABASE DESIGN</code> section explains the process of mapping entities and relationships from the ER model to tables in the relational database.</p> Signup and view all the answers

<p>The <code>CREATE TABLE</code> statements are used to define the structure of the <code>Employee</code> and <code>Department</code> tables, including the columns and their data types, as well as the primary key constraints.</p> Signup and view all the answers