While searching for an answer to another problem, I found an answer (https://stackoverflow.com/a/32634993) containing a Insert-SQL-statement with a word in single quotation marks in the attribute-enumeration. I have never seen this before. Dose it have any purpose or is it just a mistake by the author of the comment?
See " 'order' ":
INSERT INTO table_name (name_first, name_last, `order`)
VALUES (....);