# system.one {#system-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 doesn’t specify the `FROM` clause.

This is similar to the `DUAL` table found in other DBMSs.

[Original article](https://clickhouse.tech/docs/en/operations/system_tables/one) <!--hide-->