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87 lines
2.3 KiB
Markdown
87 lines
2.3 KiB
Markdown
---
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toc_title: OFFSET
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---
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# OFFSET FETCH Clause {#offset-fetch}
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`OFFSET` and `FETCH` allow you to retrieve data by portions. They specify a row block which you want to get by a single query.
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``` sql
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OFFSET offset_row_count {ROW | ROWS}] [FETCH {FIRST | NEXT} fetch_row_count {ROW | ROWS} {ONLY | WITH TIES}]
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```
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The `offset_row_count` or `fetch_row_count` value can be a number or a literal constant. You can omit `fetch_row_count`; by default, it equals to 1.
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`OFFSET` specifies the number of rows to skip before starting to return rows from the query result set.
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The `FETCH` specifies the maximum number of rows that can be in the result of a query.
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The `ONLY` option is used to return rows that immediately follow the rows omitted by the `OFFSET`. In this case the `FETCH` is an alternative to the [LIMIT](../../../sql-reference/statements/select/limit.md) clause. For example, the following query
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``` sql
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SELECT * FROM test_fetch ORDER BY a OFFSET 1 ROW FETCH FIRST 3 ROWS ONLY;
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```
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is identical to the query
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``` sql
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SELECT * FROM test_fetch ORDER BY a LIMIT 3 OFFSET 1;
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```
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The `WITH TIES` option is used to return any additional rows that tie for the last place in the result set according to the `ORDER BY` clause. For example, if `fetch_row_count` is set to 5 but two additional rows match the values of the `ORDER BY` columns in the fifth row, the result set will contain seven rows.
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!!! note "Note"
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According to the standard, the `OFFSET` clause must come before the `FETCH` clause if both are present.
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!!! note "Note"
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The real offset can also depend on the [offset](../../../operations/settings/settings.md#offset) setting.
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## Examples {#examples}
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Input table:
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``` text
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┌─a─┬─b─┐
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│ 1 │ 1 │
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│ 2 │ 1 │
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│ 3 │ 4 │
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│ 1 │ 3 │
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│ 5 │ 4 │
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│ 0 │ 6 │
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│ 5 │ 7 │
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└───┴───┘
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```
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Usage of the `ONLY` option:
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``` sql
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SELECT * FROM test_fetch ORDER BY a OFFSET 3 ROW FETCH FIRST 3 ROWS ONLY;
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```
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Result:
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``` text
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┌─a─┬─b─┐
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│ 2 │ 1 │
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│ 3 │ 4 │
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│ 5 │ 4 │
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└───┴───┘
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```
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Usage of the `WITH TIES` option:
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``` sql
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SELECT * FROM test_fetch ORDER BY a OFFSET 3 ROW FETCH FIRST 3 ROWS WITH TIES;
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```
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Result:
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``` text
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┌─a─┬─b─┐
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│ 2 │ 1 │
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│ 3 │ 4 │
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│ 5 │ 4 │
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│ 5 │ 7 │
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└───┴───┘
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```
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