What do you understand by terms ‘primary key’ and ‘secondary key’ in a database?

Yes, it is possible to see primary and secondary rainbows simultaneously. This can occur when the centres of both the rainbows coincide.

(A) Creating, (D) Managing

Column ‘A Column ‘B’ (1) RDBMS (B) Collection of interrelated  data  (2) Table  (A) Storage unit in a Relational database (3) Database designer  (D) Decides the name of the table and titles of Columns (4) Record (C) Tuple

Correct Answer - (i) 893 (ii) -56 (iii) - 80 (iv) `(33)/(20)` (v) 5505

1. Primary productivity - productivity at producer level  2. Secondary productivity – productivity at consumer level

Primary treatment involves the removal of large sized floating and suspended solids by physical methods, while secondary treatment involves decomposition of organic matter by microbial action.

(c) Foreign key

Correct answer is (b) Logical

(iii) Assertion is correct statement but reason is wrong statement.

Correct Answer - B Both (A) to (R) are correct but (R) is not correct explanation of (A).