7. The synchronization system according to claim 5 , wherein in the case that the query mechanism is the direct access mode, when the transformation status is the blocking stage, the synchronization control unit performs the database query statement in the source database; when the transformation status is the transforming stage, the storage unit stores the database query statement to form the to-be-synchronized database query statement, and the synchronization control unit performs the database query statement in the source database; when the transformation status is the completing stage and the to-be-synchronized database query statement exists in the storage unit, the synchronization control unit performs the to-be-synchronized database query statement in the target database; when the transformation status is the completing stage and the to-be-synchronized database query statement does not exist in the storage unit, the synchronization control unit performs the database query statement in the target database and the source database.
5. A synchronization system for a database transformation, comprising: a database transformer configured to transform tables from a source database to a target database; and a data adapter comprising: a statement parsing unit configured to receive a database query statement and to parse a query table related to the database query statement; a storage unit configured to temporarily store the database query statement; and a synchronization control unit configured to determine a query mechanism and to receive a transformation status of the query table returned by the database transformer, so as to perform the database query statement in the source database, the target database or both of them in accordance with the query mechanism and the transformation status; wherein the transformation status comprises is a blocking stage, a transforming stage or a completing stage; the query mechanism is a blocking transformation mode, a blocking dump mode or a direct access mode wherein in the case that the query mechanism is the blocking transformation mode, when the transformation status is the blocking stage, the synchronization control unit performs the database query statement in the source database; when the transformation status is the transforming stage, the synchronization control unit uses the storage unit to store the database query statement to form a to-be-synchronized database query statement, and the to-be-synchronized database query statement is performed in the source database when the transforming stage ends; when the transformation status is the completing stage and the to-be-synchronized database query statement exists in the storage unit, the synchronization control unit performs the to-be-synchronized database query statement in the target database; when the transformation status is the completing stage and the to-be-synchronized database query statement does not exist in the storage unit, the synchronization control unit performs the database query statement in the source database and the target database.