56 lines
2.4 KiB
Markdown
56 lines
2.4 KiB
Markdown
---
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title: SQL Select Distinct Statement
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localeTitle: SQL选择Distinct语句
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---
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## SQL选择Distinct语句
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### 介绍
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此关键字允许我们获取列中唯一值的列表。本指南将证明这一点。
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### 完整显示学生表中的数据
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```sql
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USE fcc_sql_guides_database;
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SELECT studentID, FullName, sat_score, programOfStudy, rcd_Created, 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 | programOfStudy | rcd_Created | rcd_Updated |
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+-----------+------------------------+-----------+------------------+---------------------+---------------------+
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| 1 | Monique Davis | 400 | Literature | 2017-08-16 15:34:50 | 2017-08-16 15:34:50 |
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| 2 | Teri Gutierrez | 800 | Programming | 2017-08-16 15:34:50 | 2017-08-16 15:34:50 |
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| 3 | Spencer Pautier | 1000 | Programming | 2017-08-16 15:34:50 | 2017-08-16 15:34:50 |
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| 4 | Louis Ramsey | 1200 | Programming | 2017-08-16 15:34:50 | 2017-08-16 15:34:50 |
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| 5 | Alvin Greene | 1200 | Programming | 2017-08-16 15:34:50 | 2017-08-16 15:34:50 |
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| 6 | Sophie Freeman | 1200 | Programming | 2017-08-16 15:34:50 | 2017-08-16 15:34:50 |
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| 7 | Edgar Frank "Ted" Codd | 2400 | Computer Science | 2017-08-16 15:35:33 | 2017-08-16 15:35:33 |
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| 8 | Donald D. Chamberlin | 2400 | Computer Science | 2017-08-16 15:35:33 | 2017-08-16 15:35:33 |
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| 9 | Raymond F. Boyce | 2400 | Computer Science | 2017-08-16 15:35:33 | 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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### 获取学习领域列表
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```sql
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SELECT DISTINCT programOfStudy FROM student;
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```
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```text
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+------------------+
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| programOfStudy |
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+------------------+
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| Literature |
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| Programming |
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| Computer Science |
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+------------------+
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3 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。 |