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In SQL, there are two uses of the
IN keyword, and this section
introduces the one that is related
to theWHERE clause.
When used in this context, we know
exactly the value of the returned
values we want to see for at least
one of the columns. The syntax for
using the IN keyword is as
follows:
SELECT
"column_name"
FROM "table_name"
WHERE "column_name"
IN ('value1', 'value2', ...)
The number of values in the
parenthesis can be one or more,
with each values separated by
comma. Values can be numerical or
characters. If there is only one
value inside the parenthesis, this
commend is equivalent to
WHERE "column_name" = 'value1'
For example, we may wish to
select all records for the Los
Angeles and the San Diego stores
in Table Store_Information,
Table Store_Information
| store_name |
Sales |
Date |
| Los Angeles |
$1500 |
Jan-05-1999 |
| San Diego |
$250 |
Jan-07-1999 |
| San Francisco |
$300 |
Jan-08-1999 |
| Boston |
$700 |
Jan-08-1999 |
SELECT
*
FROM Store_Information
WHERE store_name IN ('Los Angeles',
'San Diego')
Result:
| store_name |
Sales |
Date |
| Los Angeles |
$1500 |
Jan-05-1999 |
| San Diego |
$250 |
Jan-07-1999 |
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