Patent ID: 8515905

Claim:
An apparatus for maintaining databases on application servers, comprising: a database engine; data content and schema providing a logical description of the data content, the data content and schema being arranged as one of: database server files stored in an associated non-transitory memory of an associated central database server, or a self-contained executable database application archive file stored in an associated non-transitory application server of a machine independent of operating system format, and the self-contained executable database application archive file containing a first content archive file having a first version identifier and comprising a first archived staging database having contents comprising the schema and the data content provided with a first logical name, and the database engine configured to organize the first content archive file into the first archived staging database; wherein the database engine is further adapted to provide: upon the data content and schema being arranged as the database server files, conditional read/write access to the data content, and upon the data content and schema being arranged as the self-contained executable database application archive file, conditional read-only access to the data content by using the first logical name provided to the contents of the first archived staging database; wherein the database engine is further adapted to perform a controlled switchover, responsive to receipt by the associated non-transitory application server of a second content archive file containing updated newer version of contents associated with the self-contained executable database application archive file, the second content archive file having a second version identifier different than the first version identifier of the first content archive file, by: blocking formation of new database connections, closing open database connections, booting the updated newer version of contents of the self-contained executable database application archive file and, unblocking formation of the new database connections.