CIS162AD

1
CIS162AD

• Databases
• 14_databases.ppt

2
Overview of Topics

• Relational Database Terminology
• ADO.Net
• Binding data

3
Relational Databases

• Most data is now stored in relational database
  management systems (DBMS or RDBMS).
• There are various vendors to choose formOracle,
  MS SqlServer, Sybase, IBM DB2, etc.
• Visual Studio is usually used to develop
  applications that store data in Microsoft
  SqlServer.
• In this class we will use MS Access, due to
  SqlServers installation requirements.
• Those of you familiar with Access know that it
  has a built-in form and report designer.
  However, keep in mind that we would normally be
  accessing a database stored in SqlServer, which
  does not have built-in tools.

4
Database Terminology

• A database is made up of one or more related
  tables.
• Conceptually a table is made up of rows and
  columns (2D Array).
• Each row represents the data for one record(a
  person, inventory item, course information).
• Each column (field) is a data element (name,
  address, city, state, zip).
• Tables have a Primary Key Field to uniquely
  identify each record(Id number, part number,
  account number).
• Relationships between various tables can be
  defined.
• A DBMS stores everything (tables, columns,
  relationships, etc.) about the database in system
  tables.
• System and data tables are usually stored in one
  file (CSMail.mbd).

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SQL Structured Query Language

• SQL is pronounced sequel.
• SQL Structured Query Language Basic set of
  commands that are common in all DBMS.
• DBMS vendors may add additional commands.
• SQL commands are usually processed against a
  record set.
• Select name, address From customer where zip
  85202
• Delete From customer where zip 85202All rows
  matching the criteria would be selected or
  deleted.
• Record set commands are very powerful.
• Well usually want to qualified a command by
  specifying a customer id or other unique
  identifier using the Where clause.

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An Access Table
Columns
Row
7
C Application Reading Database
8
Accessing a Database ADO.Net

• Use ActiveX Data Objects (ADO)
• An Access database uses the following objects
• OleDbConnection connection tool establishes a
  link to a data source.
• OleDbDataAdapter data adapter handles
  retrieving and updating the data and creates a
  Dataset.
• Dataset bind columns in the Dataset to controls
  (textbox, listbox) by setting the DataBinding
  property.
• Use the Fill method of the data adapter to load
  the data into the dataset, daCustomer.Fill(dsCusto
  mer1) The Fill method is usually placed in the
  form load event.

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Accessing and Presenting Data
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Data Binding

• Complex Binding
• Connect more than one data element to a control.
• DataGridView uses complex binding because several
  columns from the table are displayed in the same
  control.
• Simple Binding
• Connect one data element to a control.
• Connect a textbox to the name column (etc.)
• May use Data Bindings property and select the
  column from the database that should be displayed
  in control.
• Later well build a form using Labels and
  Textboxes.

11
Completing CS13

• See assignment sheet for details.

12
Summary

• Relational Database Terminology
• ADO.Net
• Binding data