68 lines
2.7 KiB
Markdown
68 lines
2.7 KiB
Markdown
---
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title: SQL Where Clause
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localeTitle: SQL Where子句
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---
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## SQL Where子句
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### `WHERE`子句（和/或， `IN` ， `BETWEEN`和`LIKE` ）
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`WHERE`子句用于限制返回的行数。
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在这种情况下，所有这五个将被使用的是一些荒谬的`WHERE`子句。
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以下是与`WHERE`子句结果集进行比较的当前完整学生列表：
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```sql
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select studentID, FullName, sat_score, rcd_updated from student;
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```
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```text
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+-----------+------------------------+-----------+---------------------+
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| studentID | FullName | sat_score | rcd_updated |
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+-----------+------------------------+-----------+---------------------+
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| 1 | Monique Davis | 400 | 2017-08-16 15:34:50 |
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| 2 | Teri Gutierrez | 800 | 2017-08-16 15:34:50 |
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| 3 | Spencer Pautier | 1000 | 2017-08-16 15:34:50 |
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| 4 | Louis Ramsey | 1200 | 2017-08-16 15:34:50 |
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| 5 | Alvin Greene | 1200 | 2017-08-16 15:34:50 |
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| 6 | Sophie Freeman | 1200 | 2017-08-16 15:34:50 |
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| 7 | Edgar Frank "Ted" Codd | 2400 | 2017-08-16 15:35:33 |
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| 8 | Donald D. Chamberlin | 2400 | 2017-08-16 15:35:33 |
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| 9 | Raymond F. Boyce | 2400 | 2017-08-16 15:35:33 |
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+-----------+------------------------+-----------+---------------------+
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9 rows in set (0.00 sec)
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```
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行将呈现......
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* `WHERE`学生ID是1和5之间（含）
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* `OR` studentID = 8
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这是一个更新的查询，其中将不会显示具有此列表（1000,1400）中的SAT分数的任何记录：
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```sql
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select studentID, FullName, sat_score, recordUpdated
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from student
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where (studentID between 1 and 5 or studentID = 8)
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and
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sat_score NOT in (1000, 1400);
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```
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```text
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+-----------+----------------------+-----------+---------------------+
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| studentID | FullName | sat_score | rcd_updated |
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+-----------+----------------------+-----------+---------------------+
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| 1 | Monique Davis | 400 | 2017-08-16 15:34:50 |
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| 2 | Teri Gutierrez | 800 | 2017-08-16 15:34:50 |
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| 4 | Louis Ramsey | 1200 | 2017-08-16 15:34:50 |
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| 5 | Alvin Greene | 1200 | 2017-08-16 15:34:50 |
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| 8 | Donald D. Chamberlin | 2400 | 2017-08-16 15:35:33 |
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+-----------+----------------------+-----------+---------------------+
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5 rows in set (0.00 sec)
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```
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\*与所有这些SQL事物一样，它们比本入门指南中的内容更多。
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我希望这至少足以让你开始。
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请参阅您的数据库管理员手册，并自己尝试不同的选项。 |