2022-08-28 13:53:52 +00:00
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---
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2022-08-28 13:58:27 +00:00
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slug: /en/operations/system-tables/one
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2022-08-28 13:53:52 +00:00
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---
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2022-06-02 10:55:18 +00:00
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# one
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2020-06-18 08:24:31 +00:00
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This table contains a single row with a single `dummy` UInt8 column containing the value 0.
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2021-05-27 19:44:11 +00:00
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This table is used if a `SELECT` query does not specify the `FROM` clause.
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2020-06-18 08:24:31 +00:00
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This is similar to the `DUAL` table found in other DBMSs.
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2020-08-06 08:50:29 +00:00
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2020-12-03 19:27:55 +00:00
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**Example**
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```sql
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:) SELECT * FROM system.one LIMIT 10;
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```
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```text
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┌─dummy─┐
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│ 0 │
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└───────┘
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2021-07-29 15:20:55 +00:00
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1 rows in set. Elapsed: 0.001 sec.
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2020-12-03 19:27:55 +00:00
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```
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2021-09-19 20:05:54 +00:00
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[Original article](https://clickhouse.com/docs/en/operations/system-tables/one) <!--hide-->
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