doubt in select statement

[sowmyan]

in this site i saw some exercise questions so i thought to solve.
the question is to select the first name,last name and city from the table empinfo and the selected names should not belong to the city "payson"

i wrote the query and clicked submit query .but it doesn't give correct result so i saw the answer of the exercise question . the answer which i saw in that is same to that which i wrote .then y i didnt get the correct result.

whereas when i copied the query from answer and pasted in the box and clicked but this time it gives correct answer

why so???????

please reply

[rmiao]

Do you have table schema and code?