You can extract a subset of rows from a table using comparison operators. There are 6 basic comparisons.
= equal to
!= not equal to
> greater than
>= greater than or equal to
< less than
<= less than or equal to
You use these in a WHERE clause. For instance, to list all the employees who have a surname EQUAL TO 'Wright':
SELECT empno, surname, telno
FROM employee
WHERE surname = 'Wright'
Try listing the empno and salary from jobhistory where the salary is greater than or equal to 20000.
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