Chapter 10 DB System Administration Based on G. Post, DBMS: Designing & Building Business Applications University of Manitoba Asper School of Business 3500 DBMS Bob Travica Updated 2015

DBSYSTEMS Outline  Data Administrator/Analyst (DA)  Database Administrator (DBA)  DBA’s duties  DB system backup & recovery  DB system security 2 of 22

DBSYSTEMS Data Administration  Data make a valuable asset.  Data are used at many business levels  There are many databases and database systems in an organization.  Responsibility for managing data - Data Administrator (DA) or Data Analyst Employees with no mgt. powers Tactical Management Strategic Management EIS/ MIS DSS TPS Supervisory Mgt. TPS=Transaction Processing Sys. MIS=Management Info. Sys. DSS=Decisions Support Sys. EIS=Executive Info. Sys. 3 of 21 Business Operations

DBSYSTEMS Data Administration/Administrator (DA)  DA (sometimes called data architect or even business analyst) is a type of professional that resides in the IS function or in a unit interfacing with the IS function.  Focus on informing in function of business, users (reports, output forms, queries) rather than IT  Data definition and integration (e.g., Customer entity in CRM systems cutting across Sales, Marketing, R+D…).  Decision support.  Ideas for system design, involvement in system development.  Data governance and security. 4 of 21

DBSYSTEMS Database Administrator (DBA)  DBA is focused on technology.  1. DBA actively participates in DB system life cycle (plan, develop, install, manage, upgrade…).  2. DBA manages DB system:  2.1 Users: Creating user accounts, assigning use privileges  2.2 System performance: Monitoring and tuning  2.3 Backup & recovery: Supervising backups & system restoration after crashes  2.4 Security: Monitoring 5 of 21

DBSYSTEMS DBA: (1) System Planning & Design  Estimation & Design (logical, physical)  Data storage requirements, forms & reports needed (costs of development), hardware needs, matching organizational needs with DBMS products  Time, labor & cost to develop  Data modeling – coordinates with Data Analyst in the domain of logical design (e.g., class diagrams, user interface). Also DA and DBA cooperate on schemas.  In charge of physical design (types of files, access structures, DBMS product, hardware) 6 of 21

DBSYSTEMS DBA: System Development & Implementation  Defining technology standards:  Programming standards. Layout and techniques. Variable & object definition. User interface.  System testing techniques.  Loading databases.  Backup and recovery plans.  User and operator training. 7 of 21

DBSYSTEMS DBA: System Upgrade  Determines need for change  Size and speed of the DB system  Usage patterns  System output: Additional reports & queries (coop. with DA and business analysts)  Forecasting needs 8 of 21

DBSYSTEMS DBA: (2.1) Users’ Access  Control via:  1. Operating system  Access to directories  Access to files  Assigned to individuals or groups.  2. DBMS functions (Read, write, modify… data; Administer system)  9 of 21

DBSYSTEMS SQL Security Commands  GRANT privileges  REVOKE privileges  Privileges include  SELECT  DELETE  INSERT  UPDATE  Objects include  Table  Table columns (SQL 92+)  Query  Users include  Name/Group  PUBLIC GRANT INSERT ON Bicycle TO OrderClerks REVOKE DELETE ON Customer FROM Assemblers 10 of 21

DBSYSTEMS DBA: User Identification  User identification  Accounts  Individual  Groups  Passwords  Alternative identification  Finger & hand print readers  Voice…  Disposable passwords 11 of 21

DBSYSTEMS DBA: (2.2) System Performance: Performance Monitors 12 of 22

DBSYSTEMS SQL Server Query Analyzer 13 of 22

DBSYSTEMS DBA: (2.3) Database Backup  Backups are crucial!  Offsite storage needed  Types of backup  Full – in longer intervals (e.g., once a week); a copy of all tables made  Partial (Differential) – in shorter intervals (e.g., day); just new data are backed up; reduced risk but higher cost Backup Manager (part of DBMS) 14 of 21 Operational Database (Op DB) Copies Entire OpDB Backup Database (Bkp DB) Full overwrites time 1: copies new data from Op DB Partial backup time 2: copies new data from Op DB Partial backup time 3: copies final partial backup to BkP DB Bkp DB Partial grows

DBSYSTEMS DBA: 2.3 Database Recovery  Recovery needed if problems with software, hardware, incorrect user input, viruses, natural causes  Recovery = getting databases to correct state (previous example of transferring $ from savings to checking account)  Key facilities:  Recovery Manager (part of DBMS)  Transactions log (TL) file  ROLLBACK procedure  Alternative: User works with operational DB, and TL engaged only if former fails. Transaction Log (TL) (managed by Backup Manager) Recovery Manager Transactions … Savepoint Operational database copied to Transaction unfinished System crash! uses Backup databases uses recovers 15 of 22

DBSYSTEMS Transaction Log (TL) Transaction Log ID Transaction ID Pointer to previous TL record Pointer to next TL record Key TableAttribute Old value New value Database task Checkpoint (Savepoint) is when results of all new transactions are stored permanently (e.g., in Op DB). COMMIT saves changes to TL. Just the first transaction saved permanently. Recovery Mgr rolls processing back to Checkpoint and runs steps/transactions that haven’t been saved after it. 16 of 22

DBSYSTEMS DBA: (2.4) Database Security  Physical security  Protecting hardware  Protecting software and data.  Logical security  Unauthorized disclosure  Unauthorized modification  Unauthorized withholding  Security Threats  Employees (!)  Programmers  Visitors  Consultants  Business partnerships Strategic sharing EDI (Electronic Data Interchange & other inter- org. networks)  Hackers (Internet) 17 of 21

DBSYSTEMS Data Privacy A security issue Who owns data? (a governance issue) Customer rights International issues (e.g., strict privacy regulations in West Europe; Canada stricter than the US) 18 of 22

DBSYSTEMS Physical Security  Hardware-related  Preventing problems (fire, water…)  Hardware backup facilities (“Hot sites” etc.)  Telecommunication systems for backup  Personal computers challenge (use file servers for backup)  Data and software  Backups, Off-site backups (!)  Disaster planning  Plans, training & testing 19 of 21

DBSYSTEMS Managerial Controls  Insiders  Employee selection & Job termination  Monitoring suspicious behavior  Job segmentation (who can do what with data*) Physical & Logical access limitations  Outsiders  Physical access limitations  “Shadowing” 20 of 21

DBSYSTEMS Logical Security  1. Unauthorized disclosure (e.g., letting a competitor see the strategic marketing plans)  2. Unauthorized modification (e.g., letting employees change their salary figures)  3. Unauthorized withholding (e.g., preventing a finance officer from retrieving data needed to get a bank loan) 21 of 21