Managing the Data

1. Managing the Data SQL Overview

2. SQL Overview • Client\Server RDMS (relational database management system) • Commands are sent to the server and answers are returned to the client • Very efficient – low network traffic • The server does most of the work • Very stable (unsuccessful transactions rollback) • SQL is the industry standardServers

3. SQL Server • It is the only thing that touches the data • The data is under the server’s control

4. MSDE – Microsoft Desktop Engine • Freely distributable • Limited to 5 connections or less • Can be installed with ComCash

5. Microsoft SQL Server • Includes many tools • DTS – Data Transformation Services • Query Analyzer • Enterprise Manager • No connection limitation • Must be purchased and installed separately

6. Default Servervs. Named Instance • Default Server installation • Server name = computer name • Named instance (ComCash installs as a named instance) • Server name = computer name\instance name (computer name\comcash)

7. Logon and Connections • TCP/IP connections only • Default system administrator logon • Username = sa • Password = null (blank password)

8. Database • Files • .mdf file = Primary data file - stores the system tables and the data • .ldf file = Transaction log files - used to store transaction information and can be used to recover the database

9. Attached vs. Detached • Never copy, delete, rename, or move .mdf/.ldf files unless detached

10. Sample Data vs. Production • Sample data is used only for evaluation • The data can be backed up and restored to the comcash database • Live installations always use comcash (Production) database • In multiple database installations one might see comcash01, comcash02, etc

11. Tables • Rows and Columns (or records and fields) • Keys (tables typically have a key the guarantees uniqueness)