WEEK 3 : Using SQL to clean data

Question 1

SUBSTR

Answer 1

To retrieve a part of a string
SUBSTR(column, position de la lettre de départ, nombre de lettre a extraire à partir de la lettre de départ)

Question 2

LENGTH

Answer 2

To count the length of a string
LENGTH(column) > 2

Question 3

TRIM

Answer 3

To remove spaces
TRIM(column) = ‘xx’

Question 4

CAST

Answer 4

Can be used to convert anything from one data type to another (typecasting)
CAST(column AS type)