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Chapter 3: System design. System design. Creating system components Three primary components designing data structure and content create software select hardware DB to S/W to H/W input: process: output. System Design process. DB design process
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System design • Creating system components • Three primary components • designing data structure and content • create software • select hardware • DB to S/W to H/W • input: process: output
System Design process • DB design process • Development of drafts specifications based on numerous meetings, discussions, reviews, and analysis • This specifications consider reference for system design • Its include definitions, criteria, limits, formats and procedures
DB design process • Defining the DB • DB take basic responsibilities of the HR department, its include list of subjects • Developing DB require consideration of several factors such: • Data organization : categorize data according to type of files • Number and scope of records • Data elements • Field type and size • Input method • Coding • Edit and validation rules
Data sources • Data sources • From existing systems • Data from applicants employees and hr • From external resources • From other departments
Data flow • the team must focus on how data will flow through the system • Transaction flow analysis • Algorithms routines and macros • Updates • Historical data
Transaction flow analysis • Transaction flow analysis :process to make sure that the changes occur on an authorized bases • Where data come from, processed, output from considering triggering events such as: Salary change, leave of absence
Algorithms routines and macros • Set of instructions to manipulate data • Transaction processing, calculations, screen layout, table maintenance and many other activities • Algorithms :rules and mathematical calculations e.g payroll • routines :complex set of instructions including calculations and input output functions; it use auxiliary functions • macros :complicated routines e.g. monthly actions
Data Updates • To remain current, The DB must be updated by authorized users • Using transaction codes consists of 2-4 characters e.g. job information change (jIC)
Historical data • Related to data updates • Some records need to be retained of the updated data • When update such fields system sends the replaced data to a history segment • Some types of data updates trigger distribution of the outdated data to more than one history segment
Screens • Screens and menus are to guide users through choices of activities and data • Attractive screen layout maximize the ease, speed consistency of user access to data base • Menus are special types of screen
Reports • End product of the HRMS • some issues should be addressed for each report • Content (including detail or summary information) • Type (tabular, text, graphics) • Design (layout, type style, headers, and so forth) • Frequency (monthly, quarterly, and so forth) • Means of generation (automatic, as needed ; printed electronic ) • Distribution (means, quantity) • The attributes of quality information must be considered
Attributes of effective information retrieval systems • Field and constant comparisons • Search parameters equals, not equal, greater than, less than) • Arithmetic functions (addition, subtraction, multiplication, division) • Summaries and totals • Sequence levels • Variable page formatting • Table decode /explosion • Multiple detail lines • Search on multiple parameters (and /or logic) • If /then/else logic • Report cataloging and scheduling
Data control • Data control: insure that only authorized persons have access to data and only authorized procedures take place • Team should identify data security needs establish data security measures and procedures • Legal aspects of data privacy • Determining data security needs • Limit data access
Data control • Legal aspects of data privacy • HRMS must protect privacy rights of individuals • Determine what data can be viewed • Determining data security needs • HRMS must limits access to personnel data • And protection of information to be authorized access (security)
Limit data access • Access controls and codes play an important role in data security • Designers must develop access controls, and managers must maintain them after implementation • Gaining access required a written request that had to be evaluated and approved • some systems place sensitive data in a separate file or program that is accessible only to individuals having certain passwords.
HRMS specifications • DB size • Data elements • Coding structure • DB structure • Tables • Transaction flow • Screen design • Report design • data control • Linkages among various modules