Alias Table Engine

The Alias table engine is a reference to another table.

Usage in ClickHouse Server

ENGINE = Alias(database_name.table_name)
-- or
ENGINE = Alias(database_name, table_name)
-- or
ENGINE = Alias(UUID)

• The database_name and table_name parameters specify the database and the name of the referenced table.
• The UUID parameter specifies the UUID of the referenced table.

The table schema definition is prohibited for Alias table as it should always be the same as the reference table.

Example

1. Create ref_table table and alias_table table as a alias of ref_table:

create table ref_table (id UInt32, name String) Engine=MergeTree order by id;
create table alias_table Engine=Alias(default.ref_table);
create table alias_table_with_uuid Engine=Alias('5a39dc94-7b13-432a-b96e-b92cb12957d3');

2. Insert data into ref_table or alias_table:

insert into ref_table values (1, 'one'), (2, 'two'), (3, 'three');
insert into alias_table values (4, 'four');

3. Query the data:

select * from alias_table order by id;

Details of Implementation

Operations on Alias storage will be directed to its reference table.