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In the database development process,

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Below are the two methodologies used for requirement analysis phase,

1) SDA - Structured data analysis

2) SSAD - Structured systems analysis and design method

The specification documents created in requirement analysis phase are used as input to conceptual schema design phase.

For requirement analysis phase of database development process, are their any other standard methodologies(in current trend)?

overexchange
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  • Perhaps I'm being cynical, but frankly I have never seen a well-developed database requirement. Most databases (and I have had reason to access hundreds of them from many different sources - large companies, small companies, nonprofits, government agencies) appear to be designed on the basis of what screenshots we did for the application. This 100% of the time is the worst way to design a database. – HLGEM Aug 23 '17 at 16:55
  • The few well-designed database (and that would be less than 2% f the total) were designed based on the premise of what data will we need over time. In other words, what data reporting are we going to need not what data entry do we need. – HLGEM Aug 23 '17 at 16:57
  • @HLGEM In NoSql database world, it is more easy for application screenshot s mapped to mongodb document schema. But in rdbms world, is that not tough to map? – overexchange Aug 23 '17 at 18:00
  • The point is they are are not designing based on the use of the data whether relational or nosql. How do you to report on data that wasn't collected. How do you prove who changed the data when it is wrong, I need to know where the data stood at a particular point in time but the database was not designed to store the data that way because all the devs saw was the screenshot and created a field for every item on this screen. – HLGEM Aug 23 '17 at 18:08
  • And no consideration to the 5 million record imports that they want to run through a web service because they put the business rules in the application where they do not belong. Every database I have ever seen designed based on the application screenshots has data integrity issues, has performance issue, has security holes. – HLGEM Aug 23 '17 at 18:09
  • designing a database backed should never be about what is easiest. It should be about what is needed. Did you consider auditing when you mapped, How about reporting over time, large imports, security of private information etc? Mapping fields is the single worst way to design a database that exists. Database design should take as long or longer than application design because the data is going to persist long after the user interface is dead. It is the most critical part of the system and you dismiss it with well this is easier. – HLGEM Aug 23 '17 at 19:07
  • @HLGEM Practically, [DFD](https://en.wikipedia.org/wiki/Data_flow_diagram) is the result of requirement analysis phase. As mentioned [here](https://www.smartdraw.com/entity-relationship-diagram/#ERDUses), in conceptual design phase, ERD diagrams are commonly used in conjunction with a data flow diagram to display the contents of a data store – overexchange Aug 23 '17 at 22:51
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    I'm voting to close this question as off-topic because this question belongs on [Software Engineering SE](https://softwareengineering.stackexchange.com/) – Vadim Kotov Oct 26 '17 at 10:37

1 Answers1

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Waterfall lifecycles with formal requirements analysis phases are still around but they are a lot less common than they used to be. Over the last decade or so agile iterative approaches (like Scrum) have become extremely popular in place of the waterfall methods.

Your diagram illustrates some of the problems with the kind of lifecycle you are describing.

Prototyping is typically expensive and time-consuming compared to testing, inspecting and adapting a working product (although prototypes can have a role in certain circumstances).

As far as database design is concerned, up-front requirements analysis seldom yields accurate and detailed enough information to build a good database independent of other parts of the solution.

Testing is not a separate phase. It is an integral part of developing any solution.

nvogel
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