44 lines
1.0 KiB
Markdown
44 lines
1.0 KiB
Markdown
---
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title: SQL Update Statement
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localeTitle: SQL Update语句
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---
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## SQL Update语句
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要更新表中的记录，请使用`UPDATE`语句。
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小心。您可以更新表格的所有记录或仅更新一些记录。使用`WHERE`条件指定要更新的记录。可以一次更新一个或多个列。语法是：
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```sql
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UPDATE table_name
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SET column1 = value1,
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column2 = value2, ...
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WHERE condition;
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```
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以下是使用Id 4更新记录名称的示例：
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```sql
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UPDATE Person
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SET Name = “Elton John”
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WHERE Id = 4;
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```
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您还可以使用其他表中的值更新表中的列。使用`JOIN`子句从多个表中获取数据。语法是：
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```sql
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UPDATE table_name1
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SET table_name1.column1 = table_name2.columnA
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table_name1.column2 = table_name2.columnB
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FROM table_name1
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JOIN table_name2 ON table_name1.ForeignKey = table_name2.Key
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```
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以下是更新所有记录管理器的示例：
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```sql
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UPDATE Person
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SET Person.Manager = Department.Manager
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FROM Person
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JOIN Department ON Person.DepartmentID = Department.ID
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``` |