You have to connect to the database and add them using SQL syntax.  Exact steps will depend on your DB.  Here are instructions for postgres running in Ubuntu

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connect to postgres db

# sudo -u postgres psql postgres

list databases

\list

  or

\l

connect to vmail database

\connect vmail

list tables in connected database

\dt

this is the magic line

INSERT INTO alias (address, goto, domain) VALUES (‘alias.email@alias.domain.com’, ‘main.account@primary.domain.com’, ‘alias.domain.com’);

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Here are some other SQL commands that might help you:

show column names and info

\d+ alias

view all aliases

SELECT * FROM alias;

view aliases for a specific main account

SELECT * FROM alias WHERE goto=‘main.account@primary.domain.com’;

view aliases for a specific domain

SELECT * FROM alias WHERE domain=‘alias.domain.com’;

delete an alias

DELETE FROM alias WHERE address=‘alias.email@alias.domain.com’;