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“Here which of the following displays the unique values of the column? SELECT __ dept_name
FROM instructor;”

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“

Here which of the following displays the unique values of the column? SELECT ________ dept_name
FROM instructor;

Distinct

Explanation: Distinct keyword selects only the entries that are unique.

From

Name

All

“

Which of these query will display the the table given above ?
Name
Annie
Bob
Callie
Derek

July 19, 2021July 19, 2021 administrator

“

Name
Annie (Which of these query will display the the table given above ?)
Bob
Callie
Derek

Select name from employee

Explanation: The field to be displayed is included in select and the table is included in the from clause.

Select name

Select employee from name

Select employee

“

Updates that violate __________ are disallowed.

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Updates that violate __________ are disallowed.

Integrity constraints

Explanation: Integrity constraint has to be maintained in the entries of the relation.

Transaction control

Authorization

DDL constraints

“INSERT INTO instructor VALUES (10211, ’Smith’, ’Biology’, 66000);
What type of statement is this?”

July 19, 2021July 19, 2021 administrator

“

INSERT INTO instructor VALUES (10211, ’Smith’, ’Biology’, 66000);
What type of statement is this?

DML

Explanation: The values are manipulated. So it is a DML.

Query

Relational

DDL

“

DELETE FROM r; //r – relation This command performs which of the following action?

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DELETE FROM r; //r – relation This command performs which of the following action?

Clear relation entries

Explanation: Delete command removes the entries in the table.

Remove relation

Delete fields

Delete rows

To remove a relation from an SQL database, we use the ______ command.

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To remove a relation from an SQL database, we use the ______ command.

Purge

Explanation: Drop table deletes the whole structure of the relation .purge removes the table which cannot be obtained again.

Delete

Remove

Drop table

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.

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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

Explanation: Varchar changes its length accordingly whereas char has a specific length which has to be filled by either letters or spaces.

20, 4

20, 20

3, 4

The basic data type char(n) is a _ length character string and varchar(n) is _ length character.

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The basic data type char(n) is a _____ length character string and varchar(n) is _____ length character.

Fixed, variable

Explanation: Varchar changes its length accordingly whereas char has a specific length which has to be filled by either letters or spaces.

Variable, equal

Equal, variable

Fixed, equal

SELECT * FROM employee What type of statement is this?

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SELECT * FROM employee What type of statement is this?

DML

Explanation: Select operation just shows the required fields of the relation. So it forms a DML.

DDL

View

Integrity constraint

CREATE TABLE employee (name VARCHAR, id INTEGER) What type of statement is this?

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CREATE TABLE employee (name VARCHAR, id INTEGER) What type of statement is this?

DDL

Explanation: Data Definition language is the language which performs all the operation in defining structure of relation.

DML

View

Integrity constraint

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