Question

I have 2 queries I can run and will get 2 totally different results, solely because I use a “sideways single quote” versus a single quote. See below:

SELECT * FROM items WHERE 'natural' IS NOT NULL

Will return every record regardless if the “natural” column is set to NULL

SELECT * FROM items WHERE `natural` IS NOT NULL

Will correctly only return records where there are values set for the column “natural”

That ain’t right.

Answer 1

Your first example 'natural' IS NOT NULL tests to see if the string literal 'natural' is not null. Since string literals are always not null, this condition will always be true.

The second example tests the value of the column with the name natural. This is what you want.

Related

String literals

A string is a sequence of bytes or characters, enclosed within either single quote (') or double quote (") characters.

Schema object names

The identifier quote character is the backtick ( ` )