SUBSTR Function

Syntax

SUBSTR(string, start, length)
-- start: position (1-indexed)
-- length: number of characters

Examples

SUBSTR('hello world', 1, 5)  -- 'hello'
SUBSTR('hello world', 7, 5)  -- 'world'
SUBSTR('hello world', 1, 1)  -- 'h' (first character)

Your Task

Create initials from names:

• id
• first_initial: first letter of first_name
• last_initial: first letter of last_name
• full_initials: first_initial + last_initial

Clean names with TRIM before extracting. Order by id, limit to 10.