Concatenation

Question 1

What does concatenation mean?

Answer 1

Concatenation means joining two or more strings together to create a single string.

Question 2

What happens if you try to concatenate a string with a null value?

Answer 2

The entire expression will evaluate to NULL.

Question 3

What are the two ways to concatenate expressions?

Answer 3

• Use the plus sign (+)
• Use the CONCAT() function

Question 4

What happens if you try to concatenate a string with a number datatype?

Answer 4

An error will be generated

Question 5

What are the benefits of using the CONCAT() function over the other method?

Answer 5

You can concatenate numbers and strings because it converts numbers into a string format.

Results won’t return NULL even if the column has NULL values. This is because NULL is converted to an empty string with the CONCAT function.

Question 6

Using the plus sign, do you add apostrophes to numbers or to strings?

Answer 6

You would need to add apostrophes to numbers when using the plus sign concatenation technique.

Question 7

What goes inside the CONCAT() function?

Answer 7

You can add the different columns data you want to join together.