LiquiBase changeset: how do build a where clause based on ANOTHER table's column - where-clause

Question

Building upon the question How to build a WHERE-clause in a LiquiBase changeset, I would like to choose the default value of a column based on the value of a column from a different table.
For instance, I have two tables, order and order_history. Pls note that we maintain all our orders in both order in order_history as well. Once an order is completed, it is removed from order table.
order has a column 'status' but we missed it on order_history, you can call it a bad design.
How do I add 'status' to order_history now, and copy the value from the corresponding order
in order table for existing data at the time of upgrade? Is there a way to do this in liquibase?

Answer 1

If order and order_history are connected with the foreign key, then you can just do the following:
<changeSet id="foo" author="bar">
<preConditions onFail="MARK_RAN">
<and>
<columnExists tableName="order" columnName="status"/>
<columnExists tableName="order_history" columnName="status"/>
</and>
</preConditions>
<comment>Update order_history.status with values from order.status, where order.id = order_history.order_id</comment>
<update tableName="order_history">
<column name="status" valueComputed="SELECT o.status FROM order o WHERE o.id = order_id"/>
</update>
</changeSet>
If these tables are not connected, then you may use defaultValueComputed when you're adding a new column:
<addColumn tableName="order_history">
<column name="status" type="varchar(255)" defaultValueComputed="some SQL query here"/>
</addColumn>