The present invention provides a database access method, where the method includes the following steps: receiving an access request input by a client, where the access request includes at least one command statement; performing rule matching processing between the command statement included in the access request and a rule in a preset rule set, and performing transformation processing on a statement that is included in the access request and that matches the rule, so as to generate a sinking statement that satisfies an execution requirement of a data source, where the sinking statement is a statement that is delivered to a database and executed by the data source; and transmitting the sinking statement to the database to which the sinking statement points. The present invention further provides a database access apparatus and a database system to which the foregoing method is applied.