SQL

Question 1

advantages of using a database

Answer 1

1. centralised
2. less redundancy
3. concurrent access

Question 2

SELECT

Question 3

FROM

Question 4

WHERE

Question 5

LIKE

Answer 5

‘X%’
‘%X’
‘%X%’

Question 6

ORDER BY

Answer 6

ASC DESC

Question 7

LIMIT

Answer 7

how many rows to display

Question 8

GROUP BY

Answer 8

combines all rows where the specified column is the same

Question 9

AVG(x)

Answer 9

calculates the average of x

Question 9

HAVING

Answer 9

exclude certain rows from the aggregate

Question 10

MIN()

Answer 10

finds the smallest value

Question 11

MAX()

Answer 11

finds the largest valur

Question 12

SUM()

Answer 12

calculates the sum of all values

Question 13

COUNT()

Answer 13

the number of rows in the set

Question 14

AS

Answer 14

renames an aggregate column

Question 15

JOIN

Answer 15

used to gather data from more than one table

Question 16

INNER JOIN

Answer 16

only shows rows where an id matching the input was found. the intersection of the 2 tables

Question 17

FULL OUTER JOIN

Answer 17

this will display every row of both tables whether a match was found or not

Question 18

LEFT JOIN

Answer 18

display all rows from the first table & all rows with a match from the second table

Question 19

RIGHT JOIN

Answer 19

displays all rows from the 2nd table & all matching rows from the first