Syntactic Media

Syntactic Media and the Structure of Meaning

A “data structure” represents some portion of a context under which it is filled. It is a symbolic construction, by which is meant simply that it is a symbol representing some set of facts, axioms and theorems defined within some context. Without context, a data structure and its contents will have no meaning. Meaning arises from the interplay of context, procedure, and structure.

 It is understood by all persons participating in a particular context that by their mutual agreement, when they see a particular physical structure composed in “such-and-such” a manner and encountered in “this-or-that” circumstance, then this structure should inform and direct their activity in this particular way. A data structure defined explicitly in this manner may be recognizable outside of its original context, but only if it actually exists in a “broader” context.

 Within a context at a particular point in time there exists a finite set of types of physical things that are recognized in that context as being suitable “signs” from which symbols can be created. The context will, in fact, dictate what kinds of “signs” can be used, and what kinds of symbols can be created from them. The complete set of “signs” dictated in this manner is called the context’s “Syntactic Medium.”

 An Example: Different Contexts Use Different Signs

Photo of an Actual Stop Sign In Its Normal Context

Photo of an Actual Stop Sign In Its Normal Context

In the Context defined for “driving a car in the United States,” a particularly shaped, painted metal plate attached to a wooden post which has been planted in the ground at the intersection of two roads and facing toward oncoming vehicles represents the concept of a command to the oncoming motorist to “stop” their vehicle when they reach the intersection.

However, a similarly colored and shaped object, say a computer bitmap of a drawing of a “stop sign”, not only is represented by a different Syntactic Medium, it exists in an entirely different context (perhaps one that is not obviously recognized by the casual observer). If this computer bitmap “stop sign” were to

Cartoon Drawing of a Stop Sign

Cartoon Drawing of a Stop Sign

be displayed on a large computer monitor, and this computer monitor was used to replace the wood and metal Stop Sign, even if placed in the same position and orientation as the more typical structure, it is not certain that every driver would recognize the validity of the new Syntactic Medium, which could lead to accidents! This example should give the reader a clear understanding of how a Context constrains and defines the physical structures that are permitted to represent the concepts it contains.

Syntactic Media of Computers

Syntactic Media, the plural version of the term,”Syntactic Medium,” is a catch-all term for the set of representational structures recognized and/or dictated by a Context. While a single instance of a Symbol will have a single instance of a Sign which in turn will be constructed out of a single Syntactic Medium, a Context will contain many symbols which may not all be represented by the same physical structures, hence the term “Syntactic Media” will refer to the full range of physical structures available within the Context.

 By definition, “Syntactic Media” implies physical structure. Symbols need Signs, and Signs are physical. Symbols can be built on top of other Symbols. Within database management system technology, programming languages, and other related conventions, a “data type” is a symbol defining how a sequence of bytes will be manipulated by the computer. A “byte” is itself a symbol built from “bits,” which are themselves symbols whose physical manifestation may be any of the following (or many other similar structures): (a) an electrical voltage within an electrical stream traveling along a specific electrical circuit (conductive path), (b) a static or stationary magnetic field in a particular physical location on a moving physical substrate, or (c) the relative reflectivity under laser light of a particular physical location on a rotating plastic disk.

 Consider the information content of a typical, modern database contained, say, in a database management system (DBMS) such as Oracle Corporation’s Oracle 9i, Microsoft Corporation’s SQL Server 2000, or IBM Corporation’s Universal Database DB2. A single fact, say the name of a company’s top customer, is “stored” in a particular row and column of a table in this database. “Row,” “column,” and “table” are all abstract symbols. The fact is, these DBMS’s do not store their data in a tabular, physical format or pattern. In reality, the rows and columns of the table are probably physically laid out linearly (and possibly randomly) across the physical tracks of the computer’s disks. Through the operation and features of the DBMS, the appearance and behavior of rows and columns is established. Once established within the DBMS, however, these abstract symbols are used as signs (the Syntactic Medium) supporting a larger or broader context where the concept of a “top customer” is meaningful and important.

The Relational Model as Syntactic Medium

Relational DBMS’s present a Syntactic Medium defined to follow the operations, rules and “structures” of the Relational Theory defined by Codd and Date, so many years ago. From a practical sense, relational theory defines basic syntactic structures and a system of rules for their manipulation. By convention, there are standard approaches, guidelines and “best practices” for how to attach additional layers of meaning on top of this mathematical structure. The laws of the so-called “Normal Forms” represent just the start of the conventions by which the abstract structures of tables, rows and columns are imbued with additional meaning. Decades of designs in various industries has built an impressive body of conventions, practices and “design patterns” which establish sophisticated models of meaning on top of the base relational model.

 The typical approach to applying meaning to the relational model is to associate major concepts, often the major “noun-objects” of the “universe of discourse” addressed by the system, to individual tables. Hence, tables may be defined to represent such ideas as “employees,” “products,” “general ledger,” and so on. Under this convention, the database designer will almost always associate a table with the concept of a “set” of these objects. The concept of a single member of this set will most likely be signified, following this typical approach, by a single row within the table. Unlike the rows of the table which span the columns of the table, the columns of the table are rarely considered to span the rows of the table. Instead, the “set of distinct and unique values used in a column,” which is often a much smaller subset of the full complement of the values in a column of a table, may be used to define the “domain” of the column. By convention, the concepts represented by the columns are typically considered subordinate to the concepts represented by the rows. Each row is typically considered to be “constructed” from the columns, and the values contained within the columns of a single row are considered to represent various “facts” about the specific member (represented by the row) of the set of objects the table itself represents.

 The reason for this dichotomy in the treatment of rows and columns is that each column of the table will have its own name and “data type” within the relational model, while each row is considered anonymous within the relational data model context, and to contain a mixture of “data types”. Interestingly, the columns of the Relational Theory’s tables are all constructed from a single, homogenous Syntactic Medium while the rows are constructed from a heterogeneous collection of Syntactic Media!

 While this description lays out the typical way meaning is attached to the Syntactic Media provided by DBMS technology, there are notable examples where this approach is not followed. Certain types of problems have led to the establishment of additional and different syntactic layers between the Relational Theory and the ultimate meaning embodied by a database’s content. A good example of this is the discovery and promotion of the “star schema” and many similar variations which is used in so-called business intelligence applications. When this design pattern is implemented in a relational database, the rules of the “Normal Forms” may or may not be followed (often not, depending on the performance characteristics of the underlying DBMS engine).

 The “Star Schema” Pattern

In the “Star Schema” convention, DBMS tables are classified as either “Dimensions” or “Facts.” From a semantic standpoint, “dimension” tables represent categories of information useful for decomposing the measurements of interest to some analysis. Typical dimensions might include such concepts as “location,” “product,” “time,” or “organization.” Each dimension table may represent an entire hierarchy of related concepts, and each row of a dimension table would represent one path or node within such a hierarchy.

 Unlike dimension tables, “fact” tables may not have a clearly definable meaning in the terminology of the context of the analysis. The rows of the fact table will also not have such a meaning. Instead, the table as a whole will retain a meaning only in the terms of the “Star Schema” context along the lines of “the complete set of measurements for all coordinate points in an N-dimensional space defined by the unique and distinct levels within the N dimensions of the analysis.” Each row will retain a similar meaning, along the lines of “the set of measurements for a specific coordinate point within the N dimensional space defined for the analysis.” Typically, the columns of the fact table will have meaning from this analytical context, in particular each column will represent the measurement value of one analytical formula. The meaning of the association between any two columns on a single row of the fact table will generally be only the coincidence of values for their respective positions at that particular coordinate point in the dimensional space.

 All pages are Copyright (C) 2004, 2009 by Geoffrey A. Howe
All Rights Are Reserved

One Response

  1. […] since Judith knew the code to use when she found herself in trouble, she used her light as the syntactic medium in which she encoded a message of her need for help. The fact that Morse code is a globally […]

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