IE 423 – Design of Decision Support Systems Data modeling and database development

By now you should have Read Chapters 1,2,3, 4, and 5 in Pol and Ahuja Also, read chapter 6 in Pol and Ahuja

DataBase Development We have looked at ways to model data oriented problems and databases to help solve these problems The next step is to turn these models into real databases Relational models give us relational schemas,… From these we can create the actual data base

DataBase Development We are going to skip an important topic Normalization …but, will get to this topic very soon

DataBase Development Microsoft Access Relational Database Management System – RDBMS Database definition Database creation Database management Database manipulation

DataBase Development Microsoft Access Same genre of application as Oracle, DB2, MySQL, PostGres, MS SQLServer… We use it because…  Easy to use  Popular, widely used particularly in academia, small to medium sized businesses  Available  Well integrated with other MS Office applications  Supports standard data manipulation language Maybe not “industrial strength” as some

DataBase Development Microsoft Access Conceptually, everything we will learn with access will apply to other RDBMS systems… …but the techniques may be different What we will do with Access will be very migratable to other RDBMSs

DataBase Development Microsoft Access Architecture Access database is a collection of data objects In part, these data objects correspond to the entities/objects that we discussed in modeling Access has a few more that we did not discuss

DataBase Development Microsoft Access Architecture Some primary objects and concepts that we will be concerned about  Tables  Relationships  Queries  Forms and Reports

DataBase Development Microsoft Access – Work Environment Getting Started The task pane Lets you open an existing database, or Create a new one Task Pane

DataBase Development Microsoft Access – Work Environment Object Panel Shows types of Objects in database Select an object type (Tables, Queries, etc.)… Access will show you the objects of that type in the DB

DataBase Development Microsoft Access – Work Environment Object Panel Note that we have the list of existing tables in the DB, but … We also have three tools for creating a new object of that type (table)

DataBase Development Microsoft Access – Work Environment Just like Excel (and Word, and PowerPoint) we usually have two or three ways to do anything  Menus (File, Edit, Insert, Format)  Toolbars (standard, formatting, web,…)  Tool icons (DesignView, DatasheetView,…)  Key combos  Function keys You can customize toolbars  Go to View on menu bar  Click on Toolbars…, then Customize  Check each toolbar that you want to be present

DataBase Development Microsoft Access – Tables Most databases in Access (and any other RDBMS) has multiple tables A table is a RDBMS representation of a relation  (remember: 2D grid attributes and instances) Columns are attributes – we will start calling these - fields Rows are entity instances – we will start calling them records

DataBase Development Microsoft Access – Tables Work directly with tables in two modes Datasheet View or Design View Datasheet View  Shows table as a data grid  Contains columns (attributes), and…  Rows (instances or records)  Good for editing, entering data  Not so good for creating or modifying the structure of the table

DataBase Development Microsoft Access – Tables Design View  For the creation of the table  Or to view the tables definition  Two part window Top – field definitions Bottom – field properties

DataBase Development Microsoft Access – Tables Switch between Design View and Datasheet View – use View tool Or View on main menu

DataBase Development Microsoft Access – Relationships Defines relationships (clever name, huh!) between and among tables Should have some unifying field, a field in common in tables being related This is how Access will find related information

DataBase Development Microsoft Access – Relationships This is where we define  One-to-One  One-to-Many  Many-to-Many  Relations that we discussed under modeling

DataBase Development Microsoft Access – Queries There are several kinds of queries  Select Queries  Update Queries  Insert Queries  Delete Queries

DataBase Development Microsoft Access – Queries Select Queries –  Select data from other data objects  These objects can be other tables  Can be multiple tables  Can be from other queries  Can be from combination of tables and queries

DataBase Development Microsoft Access – Queries There are several kinds of queries  Select Queries  Update Queries  Insert Queries  Delete Queries

DataBase Development Microsoft Access  Select Queries – Select or pull a subset of data from a dataset  Subset may be from a single relation or from a relationship

DataBase Development Microsoft Access  Insert Queries – adds instances (records) to a relation or relationship  Add a new product to a database  Add a new path to a routing application

DataBase Development Microsoft Access  Append Queries – add sets of data to other sets of data  Add this week’s new transaction to master archive  Add a set of system access records to a master log database