TRIM, LTRIM, RTRIM in SQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the TRIM function do in SQL?

TRIM removes spaces or specified characters from both the beginning and the end of a string.

beginner

How does LTRIM differ from RTRIM?

LTRIM removes spaces or specified characters only from the start (left side) of a string, while RTRIM removes them only from the end (right side).

beginner

Write a SQL query to remove spaces from the left side of the string ' hello '.

SELECT LTRIM(' hello '); -- Result: 'hello '

beginner

Why would you use TRIM functions in a database?

To clean data by removing unwanted spaces or characters that can cause errors or mismatches in searches and comparisons.

intermediate

Can TRIM remove characters other than spaces? How?

Yes, by specifying the character to remove inside the TRIM function, for example: TRIM('x' FROM 'xxhelloxx') returns 'hello'.

What does RTRIM('hello ') return?

A 'olleh'

B ' hello'

C 'hello '

D 'hello'

RTRIM removes spaces from the right side, so trailing spaces after 'hello' are removed.

Which function removes spaces only from the left side of a string?

A TRIM

B LTRIM

C RTRIM

D REMOVE

LTRIM removes spaces from the left side only.

How do you remove the character 'x' from both ends of 'xxhelloxx'?

A TRIM('x' FROM 'xxhelloxx')

B LTRIM('x' FROM 'xxhelloxx')

C RTRIM('x' FROM 'xxhelloxx')

D REMOVE('x', 'xxhelloxx')

TRIM with 'x' removes 'x' characters from both ends.

What will TRIM(' hello ') return?

A 'hello '

B ' hello'

C 'hello'

D ' hello '

TRIM removes spaces from both ends, leaving 'hello'.

If you want to remove spaces only from the right side of a string, which function do you use?

A RTRIM

B LTRIM

C TRIM

D RIGHTTRIM

RTRIM removes spaces from the right side only.

Explain the difference between TRIM, LTRIM, and RTRIM functions in SQL.

Think about which side of the string each function cleans.

Describe a real-life situation where using TRIM functions would help clean data.

Imagine typing a name with spaces by mistake.