It is common to use database schemata to represent an abstraction of an enterprise. The populated tables of the database constitute a concrete realization of that abstraction.
At the same time, classical relational database design assumes that the schemata of base tables evolve very slowly relative to the content of the base tables. In general this works well to model most aspects of an enterprise, including its structure, because the structure of a typical enterprise evolves slowly. As a result, whenever a table needs to be changed or a new table needs to be integrated into the database, an administrator or the like performs such tasks.
In contrast to the structure of an enterprise, the state of an enterprise, as represented by the content of tables, may evolve quite rapidly. For example, consider scientific research aspects of an enterprise. One view of scientific research is that its purpose is to create new abstractions, in which measurements and observations constitute concrete instances of those abstractions. Such abstractions may be created, considered and discarded at a reasonably rapid pace. For at least this reason, relational database schemata as currently realized are not particularly good for representing such scientific (or other) abstractions that are regularly in flux.
This Summary is provided to introduce a selection of representative concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used in any way that would limit the scope of the claimed subject matter.
Briefly, various aspects of the subject matter described herein are directed towards a technology by which a database table contains rows of type data representing types, and term data representing terms that inhabit the types. Among the types are composite types (e.g., types composed of one or more ‘members’, each representing an attribute of the type), and relation types that specify relationships between types, between a type and a term, or between two terms. A composite type has a relationship with a member type according to a member definition. A relation type has a relationship with a role term according to a role definition.
In one aspect, creation of a new type of relationship is established by adding a new row to the database table representing relation types. A new instance (term) of an existing relation type may also be created. Two types, two terms, or a type and a term may have more than one relationship with one another, via two or more relation instances, each of which is of some relation type. A relationship may span database tables.
Other advantages may become apparent from the following detailed description when taken in conjunction with the drawings.
The present invention is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements and in which:
Various aspects of the technology described herein are generally directed towards using a database with types and inhabitants (terms) to accommodate the rapid evolution of data, information and knowledge. In general, the types and terms provide an environment in which any arbitrary data model may be defined and populated, without the need to alter the underlying database schemata. In this way, the database may be considered as a database of model metadata and model data, where the metadata is represented relationally.
As will be understood, the use of type systems in development contexts allows the flexible and rapid evolution of abstractions. To this end, there is provided an explicit representation of types, relationships among types and relationships between types and instances. The use of types, and terms (e.g., similar to concrete instances) that inhabit types allows adding concepts to a database without changing the underlying schema.
While the examples herein are directed towards enterprise and scientific scenarios, and while the technology is particularly beneficial with scientific data, it should be understood that any of the examples and/or applications described herein are non-limiting. As such, the present invention is not limited to any particular embodiments, aspects, concepts, structures, functionalities or examples described herein. Rather, any of the embodiments, aspects, concepts, structures, functionalities or examples described herein are non-limiting, and the present invention may be used various ways that provide benefits and advantages in computing and data processing in general.
Turning to
As described herein, there may be various types, including abstract types, sub-types, simple types (that mimic the native types of the relational database management system upon which this model may be implemented), relation types and types of composite structures. Inhabitants of types may include constants, variables, functions and composite terms.
Turning to an explicit representation of types, relationships among types and relationships between types and instances in one implementation,
In
Further, types are inhabited by a term 232, which as described above may include constants, variables, functions and composite terms.
As represented in
As represented in
A new relationship is established by adding a new row to the database table to represent a new relation type. A new instance (term) of an existing relation type may also be created. Relationships may be removed by removing rows. Relationships are simply one type of proposition that can be represented in the system. The framework can record any sort of proposition including the probability in which these propositions are likely to occur and over which span of time. In this way, the database table may change its state rapidly, without needing to change the database schema.
By way of an example filled in with simplified data,
As can be seen in this example, to model some part of an enterprise, an “Organization” node is created as a composite type, which is associated with a name member. The “works for” node is a relation type that has roles of “Organization” and “Employer.” A “Person” node is another composite type that is created in this model, is associated with a name member, and has a child node of “Employee” that inherits from the person node and is associated with an employee ID member and Title member.
It may be noted that a member definition and a role definition are nearly identical concepts. Both are associated with an “enclosing” type, are themselves of a type, and are given a name within their enclosing type. One difference is that the order of role definitions is essential to their definition whereas member definitions have no essential order. However, the distinction between members and roles reduces complexity and thus is practical to maintain in most scenarios. Moreover, in one implementation, composite type members are not ordered whereas relation type roles are ordered. For example, consider a composite type “BookAuthor” with members “Author” and “Book”. If this composite type has a display string of “is author of”, a certain automated system may be unable to differentiate between “Mary is author of Document” or “Document is author of Mary”. However, in a relation type, IsAuthorOf, “Author” is role 0, for example and “Book” is role 1, whereby the automated system knows to emit the statement “Mary is author of Document”.
Predicate logic may be used to express the nodes and their relationships, as in the following table in which the circled numerals in
As a result of the types and terms, and their relationships, it is straightforward to change the state that is represented by a database by simply adding a row to describe the updated environment, rather than changing the schema. For example, a new row may be added to a table to specify a new relationship between two nodes; similarly a row may be deleted. This is highly useful with scientific data, where new relationships are created, considered and discarded frequently. Further note that the relationships may be more than two dimensions, e.g., “Joe works for Research Group (which) is a Specially Funded Sub-group (that) is under Medical Devices” is a feasible string corresponding to three subject, predicate, object triplets.
Note that the relationship need not be known at the time the type is created. For example, consider a researcher that discovers a new type of protein. A composite type is created for the protein with appropriate terms. As the protein is further researched, its relationships with other types are discovered or hypothesized, with a relation type and appropriate role or role for that relation type added for each new relationship, simply by adding a row to the existing table.
Moreover, two types (nodes) may have multiple relationships with one another, as generally represented in
As can be seen, the explicit representation of types, including relation types and types of composite structures, along with inhabitants of types, including constants, variables, functions and composite terms, provides a database that evolves to represent concepts simply by adding or removing rows.
The invention is operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well known computing systems, environments, and/or configurations that may be suitable for use with the invention include, but are not limited to: personal computers, server computers, hand-held or laptop devices, tablet devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.
The invention may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and so forth, which perform particular tasks or implement particular abstract data types. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in local and/or remote computer storage media including memory storage devices.
With reference to
The computer 710 typically includes a variety of computer-readable media. Computer-readable media can be any available media that can be accessed by the computer 710 and includes both volatile and nonvolatile media, and removable and non-removable media. By way of example, and not limitation, computer-readable media may comprise computer storage media and communication media. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by the computer 710. Communication media typically embodies computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of the any of the above may also be included within the scope of computer-readable media.
The system memory 730 includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) 731 and random access memory (RAM) 732. A basic input/output system 733 (BIOS), containing the basic routines that help to transfer information between elements within computer 710, such as during start-up, is typically stored in ROM 731. RAM 732 typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit 720. By way of example, and not limitation,
The computer 710 may also include other removable/non-removable, volatile/nonvolatile computer storage media. By way of example only,
The drives and their associated computer storage media, described above and illustrated in
The computer 710 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 780. The remote computer 780 may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer 710, although only a memory storage device 781 has been illustrated in
When used in a LAN networking environment, the computer 710 is connected to the LAN 771 through a network interface or adapter 770. When used in a WAN networking environment, the computer 710 typically includes a modem 772 or other means for establishing communications over the WAN 773, such as the Internet. The modem 772, which may be internal or external, may be connected to the system bus 721 via the user input interface 760 or other appropriate mechanism. A wireless networking component 774 such as comprising an interface and antenna may be coupled through a suitable device such as an access point or peer computer to a WAN or LAN. In a networked environment, program modules depicted relative to the computer 710, or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation,
An auxiliary subsystem 799 (e.g., for auxiliary display of content) may be connected via the user interface 760 to allow data such as program content, system status and event notifications to be provided to the user, even if the main portions of the computer system are in a low power state. The auxiliary subsystem 799 may be connected to the modem 772 and/or network interface 770 to allow communication between these systems while the main processing unit 720 is in a low power state.
While the invention is susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents failing within the spirit and scope of the invention.