SQL中IN⽅法的使⽤
SQL: "IN" Function
The IN function helps reduce the need to use multiple OR conditions.
译：IN函数有助于减少OR条件的复合使⽤。
The syntax for the IN function is:
译：IN函数的语法：
SELECT columns
FROM tables
WHERE column1 in (value1, value2, .... value_n);
This SQL statement will return the records where column1 is value1, , or value_n. The IN function can be used in any va
sql中delete用法
译：该SQL语句将返回column1的值是value1, , 或者value_n的记录。IN函数可以⽤于任何合法的SQL语句中－
select, insert, update, or delete。
Example #1
The following is an SQL statement that uses the IN function:
译：下⾯是⼀个使⽤IN函数的SQL语句
SELECT *
FROM supplier
WHERE supplier_name in ( 'IBM', 'Hewlett Packard', 'Microsoft');
This would return all rows where the supplier_name is either IBM, Hewlett Packard, or Microsoft. Because the * is used in the se
译：这将返回supplier_name为IBM, Hewlett Packard, 或者 Microsoft的所有记录。因为在SELECT中使⽤了*，supplier表中所有的字
段都会显⽰在结果集中。
It is equivalent to the following statement:
译：与下⾯的SQL语句相同：
SELECT *
FROM supplier
WHERE supplier_name = 'IBM'
OR supplier_name = 'Hewlett Packard'
OR supplier_name = 'Microsoft';
As you can see, using the IN function makes the statement easier to read and more efficient.
译：正如你所看到的，使⽤IN函数使语句更容易读并且有更⾼的执⾏效率。
Example #2
You can also use the IN function with numeric values.
译：你也可以同数字使⽤IN函数
SELECT *
FROM orders
WHERE order_id in (10000, 10001, 10003, 10005);
This SQL statement would return all orders where the order_id is either 10000, 10001, 10003, or 10005.
译：将返回所有order_id是10000, 10001, 10003, 或者10005的记录
It is equivalent to the following statement:
译：与下⾯的SQL语句相同：
SELECT *
FROM orders
WHERE order_id = 10000
OR order_id = 10001
OR order_id = 10003
OR order_id = 10005;
Example #3 - "NOT IN"
The IN function can also be combined with the NOT operator.
译：IN函数可以和NOT操作符连⽤
For example,
SELECT *
FROM supplier
WHERE supplier_name not in ( 'IBM', 'Hewlett Packard', 'Microsoft');
This would return all rows where the supplier_name is neither IBM, Hewlett Packard, or Microsoft. Sometimes, it is more efficie
译：这将返回supplier_name不是IBM, Hewlett Packard，及Microsoft的所有记录。有时，与你想要的数据相反，这样可以更有效的例出
你不需要的值。

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