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 does not specify the FROM
clause.
This is similar to the DUAL
table found in other DBMSs.
Example
:) SELECT * FROM system.one LIMIT 10;
┌─dummy─┐
│ 0 │
└───────┘
1 rows in set. Elapsed: 0.001 sec.
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