Lecture 19

Question 1

Query to create a schema

Answer 1

CREATE SCHEMA creates a schema.
CREATE SCHEMA COMPANY AUTHORIZATION ‘John_Smith’ ;

Question 2

The main command for data definition is

Answer 2

CREATE

Question 3

SQL uses the terms ….. for the formal relational model terms

Answer 3

table, row and column

Question 4

Query to create a relation

Answer 4

CREATE TABLE ; - they are called base tables

Question 5

numeric data types

Answer 5

INTEGER, SMALLINT, REAL DOUBLE PRECISION, FLOAT, DECIMAL(P, D)

Question 6

Boolean

Answer 6

TRUE FALSE UNKOWN

Question 7

character-string

Answer 7

CHAR(N), VARCHAR(N)

Question 8

bit-strings

Answer 8

BIT(N), VARBIT(N)

Question 9

large object types?

Answer 9

blob - binary large object, clob - character large object

Question 10

When a query returns a large object…

Answer 10

a pointer is returned rather than the large object itself

Question 11

how to define domain

Answer 11

CREATE DOMAIN AIRPORT-CODE CHAR(3);
CREATE DOMAIN FLIGHTNUMBER CHAR(5);

Question 12

what query does not allow null

Answer 12

NOT NULL

Question 13

secification of a default value

Answer 13

DEFAULT<value></value>

Question 14

how to check a specific constraint

Answer 14

CHECK
EX: INT NOT NULL CHECK (Dnumber > 0 AND Dnumber < 21)

Question 15

How to define primary ot foreign key

Answer 15

(FOREIGN KEY) PRIMARY KEY
INT PRIMARY KEY or PRIMARY KEY(Dnumber)

Question 16

What to use to make delete data from other tables where it is foreign key

Answer 16

FOREIGN KEY(Dno) REFERENCES DEPARTMENT(Dnumber) ON DELETE
SET DEFAULT ON UPDATE CASCADE;