1. A method for processing a data definition language (DDL) statement that specifies an operation to build an index based on a particular table, the method comprising: receiving the DDL statement; based on the DDL statement, building the index; while building the index, receiving a plurality of data manipulation language (DML) statements that each specify one or more changes to the particular table; recording the specified changes in a journal table; after the index is built, receiving a particular DML statement that specifies a particular change to the particular table; determining that one or more changes of the specified changes recorded in the journal table would affect the same data in the index that the particular change would affect if the particular change were applied to the index; in response to determining that one or more changes of the specified changes recorded in the journal table would affect the same data in the index, performing at least one of the following: (a) applying the one or more changes of the specified changes to the index, or (b) deleting the one or more changes of the specified changes; and applying the particular change to the index.