43 lines
1.2 KiB
Markdown
43 lines
1.2 KiB
Markdown
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title = "UPDATE"
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UPDATE
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======
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Synopsis
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--------
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``` sql
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UPDATE table_name SET column_name = expression[, column_name = expression, ... ] [ WHERE condition ]
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```
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Description
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-----------
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`UPDATE` changes the values of the specified columns in all rows that satisfy the condition. Only the columns to be modified need be mentioned in the SET clause; columns not explicitly modified retain their previous values.
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Examples
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--------
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Update table `users`, change the name `Francisco` where the `id` equal to 1:
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```sql
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UPDATE users SET name = 'Francisco' WHERE id=1;
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```
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Limitations
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-----------
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- Right now only Hive Connector and transactional ORC table support `UPDATE`.
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- The set expression does not support subquery.
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- Direct column reference is supported, but NOT expression with column reference.
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- `UPDATE` cannot be applied to view.
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- `UPDATE` dose not support implicitly data type conversion, please use `CAST` when value does not match target column's data type.
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- If the table is partitioned and/or bucketed, bucket\_column and partition column cannot be updated. i.e They cannot be target of SET expression.
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See Also
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--------
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[insert](./insert.html), [insert-overwrite](./insert-overwrite.html) |