ClickHouse/docs/en/operations/system-tables/one.md
2023-01-11 10:08:11 -05:00

25 lines
454 B
Markdown

---
slug: /en/operations/system-tables/one
---
# one
This table contains a single row with a single `dummy` UInt8 column containing the value 0.
This table is used if a `SELECT` query does not specify the `FROM` clause.
This is similar to the `DUAL` table found in other DBMSs.
**Example**
```sql
SELECT * FROM system.one LIMIT 10;
```
```response
┌─dummy─┐
│ 0 │
└───────┘
1 rows in set. Elapsed: 0.001 sec.
```