Create a table studmarks with following attributes name and data type.

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Create a table studmarks with following attributes name and data type Create a table studmarks with following attributes name and data type:

Rollno number (6), Regnumb number(14), semester number(1), cgpa number (5) and perform some other operations.

QUERY*

Create table studmarks (rollno number(6), regnumber number(14), semester number(1), cgpa number(5));

Desc studmarks;

As Shown Fig...2.1

Fig... 2.1
    Alter the table:
  1. Add the constraints UNIQUE for regnumber attribute from table.
    2. QUERY*

    Alter table studmarks modify (regnumber number(14) UNIQUE);

    As Shown Fig...2.2

    Fig... 2.2
  2. Remove the constraints for the regnumber attribute.
  3. Modify the data type of regnumber to varchar(16).

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