TPS data collection
- Transaction data is immediately stored into transaction logs and then completed transactions are stored in the master file in the server.
- Data is collected on:
- time of transaction
- price points
- payment method
- users data, their name, billing address and credit card details
- collecting user input such as scanning barcodes
Real time vs Batch processing
Similarities
- carry out transactions for the user
- both use collecting and storage
Differences:
- RT —> completes individual transactions immediately after they have been initiated
- BP —> use bulk transactions after data has been collected from the individuals, delay in the transaction (transactions take time to actually be completed)
- RT —> can do face to face
- BP —> can not do face to face
- RT —> can handle errors immediately during transactions
Real Time transactions steps
- Data collection is split into a sequence of forms
- Raw data collection
- Preparation
- Sorting
- Processing Analysis
- Output
- Storage
Storing and Retrieving in TPS
- records of the collected user transaction details are stored in the transaction file
- processed transactions are stored in the master file containing all committed transactions
OLAP
Online Analytical Processing,
analyses data in a multi-dimensional view
e.g. information from different locations can be compared
Storage media to backup systems
- external hard drives
- tape drives
RFID tags
RFID –> radio frequency identification
- Uses radio waves to identify people or objects
Tape drives
- Can store more data than external hard drives
- Can be stored onsite or offsite
- Very economical as compared to external hard drives
External Hard Drives
- Easy to use
- Easily transportable
- Can be stored onsite or offsite
- Secure and do not rely on cloud storage which can go offline
Full backups
- copy of ALL data within the system
can be a complete image of the entire hard disk - most businesses perform full backups of all their data files on a regular basis
Advantages of Full Backups
Not a complicated process, very simple to perform
Disadvantages of Full Backups
Copying all files takes a large amount of storage
Copying all files takes a long time
Archive Bits
file component that indicates when new changes have been made to files and when new files are created
Checkpoints (in backups)
checkpoint record in the recovery process contains information necessary to restart the system
Grandfather Father Son Backup method
uses three generations of backup master files to back up the master files in a transaction processing system
son - daily (at the end of each day)
father - weekly (at the end of each week)
grandfather - monthly (at the end of each month)
Onsite storage
Immediate access to data
Offsite storage
Provides access to data in any location
Why systems would require real-time processing
if concurrency is required in the system
Why systems would require batch processing
if transactions are issued/committed periodically and it is impractical to commit transactions individually
List the characteristics of a TPS
- Rapid Response
- Reliability
- Inflexibility
- Controlled processing
Requests in a TPS
where a question or trigger to the transaction is initiated, e.g. swiping an ATM card to start a transaction
Importance of data warehouses for TPS
a resource that can be accessed by analysis tools to analyse its transaction data
allows data from TPS to be analysed in isolation to minimise impact on the TPS
Partial backups
stores only new or recently changed files
Advantages of partial backups
- space saving
- places less demand on network bandwidth
- scheduling of backups is more flexible
