data-architecture-a
Chapter 7.3 Data Modeling for the Structured Environment Abstract The genesis of much data is the operational environment. As tr ...
The data that are modeled are the data that sit at the heart of the business of the company. The data model is shaped around wha ...
Fig. 7.3.1 Separating detailed and summarized data. After the granular data are identified, the next step is to “abstract” the d ...
The highest level of abstraction for the data model is called the entity relationship diagram (ERD). The ERD reflects data at it ...
The next level of the data model is the place where much detail is found. This level of the data model is called the “data item ...
Fig. 7.3.5 A simple dis. The anchor or primary data are indicated by the box of data that is at the top left of the diagram. The ...
Physical Data Base Design Once the dis is created, the physical design of the dis is created. Each grouping of data in the dis r ...
Fig. 7.3.7 The elements of a database. The elements of the database design include keys, attributes, records, and indexes. Relat ...
Chapter 7.3: Data Modeling for the Structured Environment ...
Fig. 7.3.8 Different levels of modelling. In Fig. 7.3.8, it is seen that the ERD is the equivalent to a globe of the world. The ...
Chapter 7.3: Data Modeling for the Structured Environment ...
Fig. 7.3.9 The sequence of the steps in doing database design. Generic Data Models It has been noticed that when a data model is ...
Chapter 8.1 A Brief History of Data Architecture Abstract Data architecture began with simple storage devices. But soon, the nee ...
Fig. 8.1.1 The world of data architecture. The simplest evolution that has occurred (and has been described in many places) is t ...
Fig. 8.1.2 The physical dimension of data architecture. The beginning of the computer industry harks back to paper tape and punc ...
Fig. 8.1.3 Punched cards and paper tape. Next came magnetic tape. Magnetic tape could store much more data than could ever be st ...
dropped significantly, the capacity increased, and the speed of access decreased. Disk storage was a superior alternative to mag ...
Fig. 8.1.7 shows the symbol for big data. Fig. 8.1.7 Big data. Over the years then, the total amount of data that could be manag ...
Fig. 8.1.8 The logical linkage of data. In the very earliest days, data were logically organized in almost a random fashion. Eve ...
Fig. 8.1.9 is a symbol depicting the Yourdon approach to structured programming and development. Fig. 8.1.9 A networked data str ...
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