43 lines
1.1 KiB
Markdown
43 lines
1.1 KiB
Markdown
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---
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title: SQL Update Statement
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---
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## SQL Update Statement
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To update a record in a table you use the `UPDATE` statement.
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Be careful. You can update all records of the table or just a few. Use the `WHERE` condition to specify which records do you want to update. It is possible to update one or more columns at a time. The syntax is:
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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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Here is an example updating the Name of the record with Id 4:
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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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You can also update columns in a table by using values from other tables. Use `JOIN` clause to get data from multiple tables. The syntax is:
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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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Here is an example updating Manager of all records:
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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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```
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