Method and apparatus for obtaining an identifier for a logical unit of data in a database

A method of obtaining a first identifier of a logical unit of data that belongs to a database, the first identifier uniquely identifying a location of the logical unit of data within the database, the logical unit of data having an application space label which can be used by application programs to access the logical unit of data from the database, the method comprising a step of:

• (A) requesting the database to provide the first identifier without first accessing the logical unit of data from the database using the application space label.

A computer readable medium encoded with a computer program for execution on a host computer that includes a database, the computer program, when executed on the host computer, performing a method of obtaining a first identifier of a logical unit of data that uniquely identifies a location of the logical unit of data within the database, the method comprising a step of:

• (A) determining a group of identifiers that includes the first identifier based upon information concerning a structure of the database, wherein the information does not directly specify the group of identifiers.

A computer readable medium encoded with a computer program for execution on a host computer that includes a database, the computer program, when executed on the host computer, performing a method of obtaining a first identifier of a logical unit of data that belongs to the database and uniquely identifies a location of the logical unit of data within the database, the logical unit of data having a label in application space by which the logical unit of data can be accessed from the database, the method comprising a step of:

• (A) requesting the database to provide the first identifier without first accessing the logical unit of data from the database using the label in application space.