Question

a) identify the primary key of the Book Table, also mention the suitable reason for choosing it as a primary key .

b) difference between:
i. char and varchar data type
ii. DDL and DML
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Answer 1

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(a) Primary key of the table BOOK can be : BOOK ID

Reason for choosing it as the primary key: As, it can uniquely define each record of the table.

(b) DIFFERENCE BETWEEN CHAR AND VARCHAR:

Char: (i) stores content exactly up to the length specified by the user.

(ii) pads with treiling spaces for shorter strings.

Varchar: (i) stores up to the length specified by the user.

(ii) no pedding with extra spaces.

DIFFERENCE BETWEEN DDL AND DML:

DDL: (i) Full form: Data Definition Language

(ii) function: deals with the modification in the structure of the table.

DML: (i) Full form: Data Manipulation language

(ii) function: deals with the modification in the records of the table.

Hope it Helps!!