eolas/zk/Update_existing_data_in_SQL_table.md

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---
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tags:
- SQL
- databases
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---
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# Update existing data with the SQL `UPDATE` command
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We use `UPDATE` to modify existing records in our table.
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## Schematic syntax
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```sql
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UPDATE [table_name]
SET [field]
WHERE [conditional expression/filter]
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```
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## Example
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```sql
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UPDATE manufacturer
SET url = '<http://www.hp.co.uk>'
WHERE manufacturer_id = 4; --typically this will be the primary key as you are updating and existing record and need to identify it uniquely
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```
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## Update multiple fields
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```sql
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UPDATE manufacturer
SET url = '<http://www.apple.co.uk>',
year_founded = 1977
WHERE manufacturer_id = 2;
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```