dbms mcq:
1. Which one of the following is used to define the structure of the relation, deleting relations and relating schemas?
9. CREATE TABLE employee (name VARCHAR, id INTEGER)
1. Which one of the following is used to define the structure of the relation, deleting relations and relating schemas?
- DDL(Data Definition Langauge)
- DML(Data Manipulation Langauge)
- Relational Schema
- Query
2. Which one of the following provides the ability to query information from the database and to insert tuples into, delete tuples from, and modify tuples in the database?
- DDL(Data Definition Langauge)
- Query
- Relational Schema
- DML(Data Manipulation Langauge)
3. The basic data type char(n) is a _____ length character string and varchar(n) is _____ length character.
- Fixed, variable
- Equal, variable
- Fixed, equal
- Variable, equal
4. An attribute A of datatype varchar(20) has the value “Avi”. The attribute B of datatype char(20) has value ”Reed”. Here attribute A has ____ spaces and attribute B has ____ spaces.
- 3, 20
- 4,5
- 23,4
- 2,5
5. To remove a relation from an SQL database, we use the ______ command.
- Drop table
- Remove
- Delete
- Purge
6. DELETE FROM r; //r - relation
This command performs which of the following action?
- Clear relation entries
- Delete rows
- Delete coulomb
- Delete fields
7. INSERT INTO instructor VALUES (31932, ’Smith’, ’Biology’, 78000);
What type of statement is this?
- Relational
- DML
- Query
- DDL
8. Updates that violate __________ are disallowed.
- Integrity constraints
- Transaction control
- DDL constraints
- Authorization
What kind of statement is this?
- DDL
- Query
- Relational
- Integrity constraint
10. SELECT * FROM employee
What type of statement is this?
- Query
- Integrity constraint
- View
- DML