Table aliasing is a new feature letting you define an alias on a table. This alias can be used in every SQL statement to reference the underlying table. In the Developer Console, the alias will appear next to the table.
Alias is defined in the schema of the underlying table
How to set an alias on a table?
You can set an alias by using the following SQL statement :
ALTER TABLE nyc_yellow SET ALIAS myAlias;
How to drop an alias from a table?
You can drop an alias by using the following SQL statement :
ALTER TABLE nyc_yellow DROP ALIAS myAlias;