1. A machine-readable storage device having machine readable instructions tangibly stored thereon which when executed by the machine, cause the machine to perform a method to apply database schema changes to a report, the method comprising: detecting a change in a database schema; receiving one or more changes between a first database schema relevant to a first database state and a second database schema relevant to a second database state; and applying the one or more changes to the report by: generating a parse tree having nodes and leaves relevant to the first database state, wherein the parse tree comprises syntactic structure of a first statement reflecting the first database state; modifying the generated parse tree to include the one or more changes between the first database schema and the second database schema by modifying the nodes and the leaves to reflect the second database state; and traversing the modified parse tree to generate a second statement to modify the report to reflect the second database schema relevant to the second database state.