Answer:
SELECT
CardNumber,
len(CardNumber) as CardNumberLength,
right(CardNumber, 4) as LastFourDigits,
'XXXX-XXXX-XXXX-' + right(CardNumber, 4) as FormattedNumber
from Orders
Explanation:
The question you posted contains the answer (See answer section). So, I will only help in providing an explanation
Given
Table name: Orders
Records to select: CardNumber, length of CardNumber, last 4 digits of CardNumber
From the question, we understand that the last four digits should display the first 12 digits as X while the last 4 digits are displayed.
So, the solution is as follows:
SELECT ----> This implies that the query is to perform a select operation
CardNumber, ---> This represents a column to read
len(CardNumber) as CardNumberLength, -----> len(CardNumber) means that the length of card number is to be calculated.
as CardNumberLength implies that an CardNumberLength is used as an alias to represent the calculated length
right(CardNumber, 4) as LastFourDigits, --> This reads the 4 rightmost digit of column CardNumber
'XXXX-XXXX-XXXX-' + right(CardNumber, 4) as FormattedNumber --> This concatenates the prefix XXXX-XXXX-XXXX to the 4 rightmost digit of column CardNumber
as FormattedNumber implies that an FormattedNumber is used as an alias to represent record
from Orders --> This represents the table where the record is being read.
