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freeCodeCamp/guide/chinese/sql/sql-in-operator/index.md
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---
title: SQL In Operator
localeTitle: SQL In Operator
---
## SQL In Operator
## IN运营商定义
`IN`运算符用于`WHERE``HAVING` (作为`GROUP BY`一部分以将所选行限制为列表中的项“IN”。
以下是与`WHERE`子句结果集进行比较的当前完整学生列表:
```sql
select studentID, FullName, sat_score, rcd_updated from student;
```
```text
+-----------+------------------------+-----------+---------------------+
| studentID | FullName | sat_score | rcd_updated |
+-----------+------------------------+-----------+---------------------+
| 1 | Monique Davis | 400 | 2017-08-16 15:34:50 |
| 2 | Teri Gutierrez | 800 | 2017-08-16 15:34:50 |
| 3 | Spencer Pautier | 1000 | 2017-08-16 15:34:50 |
| 4 | Louis Ramsey | 1200 | 2017-08-16 15:34:50 |
| 5 | Alvin Greene | 1200 | 2017-08-16 15:34:50 |
| 6 | Sophie Freeman | 1200 | 2017-08-16 15:34:50 |
| 7 | Edgar Frank "Ted" Codd | 2400 | 2017-08-16 15:35:33 |
| 8 | Donald D. Chamberlin | 2400 | 2017-08-16 15:35:33 |
| 9 | Raymond F. Boyce | 2400 | 2017-08-16 15:35:33 |
+-----------+------------------------+-----------+---------------------+
9 rows in set (0.00 sec)
```
将显示在此列表中具有SAT分数的行1000,2400
```sql
select studentID, FullName, sat_score, rcd_updated
from student
where sat_score in (1000, 2400);
```
```text
+-----------+------------------------+-----------+---------------------+
| studentID | FullName | sat_score | rcd_updated |
+-----------+------------------------+-----------+---------------------+
| 3 | Spencer Pautier | 1000 | 2017-08-16 15:34:50 |
| 7 | Edgar Frank "Ted" Codd | 2400 | 2017-08-16 15:35:33 |
| 8 | Donald D. Chamberlin | 2400 | 2017-08-16 15:35:33 |
| 9 | Raymond F. Boyce | 2400 | 2017-08-16 15:35:33 |
+-----------+------------------------+-----------+---------------------+
4 rows in set (0.00 sec)
```