Data and knowledge management

Data and knowledge management

1. The data hierarchy

   • Bit: smallest unit of data (0,1)
   • Byte:8 bits; single character
   • Field:logical groping of characters into a word

2. difficulties of managing data

   • exponentially
   • devices and methods
   • degrate overtime
   • rot

3. big data

   • defination
     • exhibit variety;high velocit; not fit; sophisticated IS
   • Issues
     • untrusted sources
     • dirty
     • change

4. data warehouse

   • characteristics
     • Integrated
     • Time variant
     • Nonvolatile
     • Multidimensional structure
     • organized by business dimension or subject
     • Online anlytical processing
     • data mining
   • advantage
     • access data quickly
     • conduct extensive analysis
     • consolidated
   • disadvantage
     • high cost
     • constantly maintencance
     • high security

5. master data management

   • spans all of organization's business process
     • store, maintain & exchange

6. data management system

   • minimize
     • data redundancy
     • data isolation
     • data inconsistency
   • maximize
     • data integrity
     • data independency
     • data security
   • DBMS:tools to crate and manage a database
   • SQL:requesting purpose
     • select
     • from
     • where
   • relational database
     • two-dimensional table
     • flat file
     • be organized
     • advantage
       • compare information quickly
       • retrieve item
     • disadvantage
       • slow search and long access time
     • entity
       • person, place, thing & event
     • Instance
       • specific, unique of entity
     • Primary key
       • uniquely identifies
     • secondary key
       • not identify the record with complete accuracy
     • Foreign key
       • identifies a row of another table
   • Attribute/Field
     • characteristic/ quality
   • Normalization
   • data dictionary
   • features

7. Knowlege management

   • explicit knowledge
   • tacit knowledge
   • Benefit
     • best practice
     • improve
   • challenges
     • share tacit
     • updated
     • invest
   • cycle
     • create
     • capture
     • refine
     • store
     • manage
     • disseminate

8. ER

   • one to one
   • one to many
   • many to many