Condition

An expression can be any of the following:

• A number
• A column in a table or view
• A string literal, such as 'Maple Street'
• A built-in function, such as concat('Learning', ' ', 'SQL')
• A subquery
• A list of expressions, such as ('Boston', 'New York', 'Chicago')

The operators used within conditions include:

• Comparison operators, such as =, !=, <, >, <>, like, in, and between
• Arithmetic operators, such as +, −, *, and /

Condition Evaluation

Using Parentheses

where (first_name = 'STEVEN' or last_name = 'YOUNG')
	and create_date > '2006-01-01';

Not Operator

where not (first_name = 'STEVEN' or last_name = 'YOUNG')
	and create_date > '2006-01-01';

where (first_name <> 'STEVEN' and last_name <> 'YOUNG')
	and create_date > '2006-01-01';

Condition Types

Equality

DELETE FROM rental
WHERE year(rental_date) = 2004;