CBSE · 083Class XII · 2023Section E2 marks

Question 34(3or)

30 March 2023 · Computer Science (083)

(iii) Write the statements to : (a) Add a constraint PRIMARY KEY to the column LABNO in the table LAB. (b) Delete the table LAB.

Answer

(a)

sql

ALTER TABLE LAB ADD PRIMARY KEY (LABNO);

(b)

sql

DROP TABLE LAB;

Explanation

(a) ALTER TABLE ... ADD PRIMARY KEY attaches a primary-key constraint to an existing column. (b) DROP TABLE removes both the table structure and its data permanently.