In is a special kind of operator which uses with where clauses. In the where expression only one value is allowed to be sent through the query. With help of in operator you can send multiple values in the where clause.
The syntax of IN keyword is as follows:
WHERE "column_name" IN ('value1', 'value2', ...)
Let's you wish to select all records for the Los Angeles and the San Diego stores in Table Store_Information,
The Values inside parenthesis can be one or more, with each values separated by comma. Values can be characters or numerical. If there is only one value inside the parenthesis, then command is equivalent to :-
WHERE "column_name" = 'value1'
WHERE store_name IN ('Los Angeles', 'San Diego')