12.7. SQL: in, between, like, and is null Operators

This section examines four special operators (other than the comparators =, <, etc.) that SQL provides for use within search conditions: in; ...between...and...; like and is null. These are sometimes called functions, and the conditions they are used to express are called “predicates” in the SQL standard.

A function is something that takes zero or more values as arguments and returns a single value as its result. You are probably familiar with functions from mathematics or programming, such as cos (x) or sqrt (x). As these examples illustrate, syntactically a function is usually represented as a function identifier preceding its arguments, which are typically included in parentheses.

When the ...

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