Abstract: A database system comprising a node value stored in a first electronic data memory device sector. A lock state and access visa associated with the node value, such that if the visa is non-zero, the visa must be presented to access the node. A notification field associated with the node value, the notification field stored in a second electronic data memory device sector. An update processor configured to electronically retrieve and process the notification field if the node value is modified.

Abstract: A database system comprising a node value stored in a first electronic data memory device sector. A lock state and access visa associated with the node value, such that if the visa is non-zero, the visa must be presented to access the node. A notification field associated with the node value, the notification field stored in a second electronic data memory device sector. An update processor configured to electronically retrieve and process the notification field if the node value is modified.

Abstract: A persistent data storage system comprising a code development system for defining a plurality of memory storage device identifiers. A configuration database system for associating a tag with a database storage address and with one of the memory storage device identifiers. The code development system for recovering data stored in a persistent electronic data memory associated with each of the memory storage device identifiers during initialization of a database. The configuration database for causing code developed by the code development system to cause data stored at the database storage address to be stored in the persistent electronic data memory if the data stored at the database storage address is changed.