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Advantage .NET Data Provider agenda • ADO.NET Overview • Advantage .NET Data Provider • Advantage Specific Functionality ADO.NET architecture ADO.NET objects • Connection – Connects to the data source • DataAdapter – Connects through OConnection and populates DataSet • Command – Executes SQL or stored procedures against datasource • DataReader – Provides read-only connections to datastore data adapter • Data Adapter fills DataSet by using built-in Command Objects – SelectCommand – DeleteCommand – UpdateCommand – InsertCommand • Data Adapter’s update method flushes changes to datasource via Delete, Update and Insert Commands data reader • DataReader object automatically holds results from a Data Command • DataReader object returns a read-only, forwardonly stream of data from a DataCommand. Only a single row of data is in-memory at a time. dataset architecture dataset • Miniature Database – Made up of tables and relationships between tables – Set up constraints and referential integrity • DataSets are disconnected – Other users may change underlying data – DataSets have no recognition of changes datatable • A single table within a dataset • Contains all table data and schema • Constraint collection – Foreign Key – Unique Advantage .NET Data Provider connection string • Free table connection AdsConnection conn = new AdsConnection( "data source=C:\\data;ServerType=remote |local; TableType=ADT" ); • Data Dictionary connection AdsConnection conn = new AdsConnection( "data source=C:\\data\mydictionary.add ;ServerType=remote|local;User ID=chrisf ;Password=password"); • Reminder: ADSSYS account for data dictionary Administration only Advantage specific options • • • • • • • • Server Type Table Type Encryption Password TrimTrailingSpaces Compression CharType LockMode SecurityMode quick start* • Add a reference to Advantage.Data.Provider • Specify the name space using Advantage.Data.Provider; ( C# ) Imports Advantage.Data.Provider ( VB.NET ) • • • • Define the connection string Create an AdsDataAdapter Create a DataSource Bind controls to the DataSource Advantage data adapter wizard* • Added with version 7.0.1 • Creates all the required objects – Connection – DataAdapter – SQL Commands • Allows for data preview Dealing With Concurrency • Last in Wins – Ok if reading one record at a time – Not for sensitive Inventory/Ticket applications • Version Number Approach – UPDATE Table1 Set Column1 = @newvalue1, Column2 = @newvalue2 WHERE RowVersion = @origRowVersionValue • Saving All Values Approach – UPDATE Customers SET CustomerID = @currCustomerID, CompanyName = @currCompanyName WHERE ( CustomerID = @ origCustomerID ) AND ( CompanyName = @origCompanyName OR @origCompanyName IS NULL and CompanyName IS NULL ) Advantage Specific Functionality Adsconnection* • • • • • • • Connection Timeout Database Dictionary Version Is Dictionary Connection Server Name Server Time Server Type AdsExtendedDataReader • • • • • • • Filters Index Support Record Number Ranges Table Encryption Record Locking Copying Tables locating records* • Seek Types – Soft Seek – Hard Seek – Seek Last – Seek GT • Seek syntax Reader.Seek( New Object { <value> }, SeekType ) Borland Data Provider • The Borland Data Provider (BDP) is a new data access method available in C# Builder and Delphi 8 • Requires Delphi 8 General Update 2 • Add Advantage information to bdpDataSources.xml for use in the IDE summary • ADO.NET • Advantage Data Provider – Advantage Connection – Advantage DataAdapter – Advantage DataReader – Advantage ExtendedDataReader • Borland Data Provider Questions ? ? ? Advantage Database Server: The Official Guide (ISBN 0-07223084-3) is a new book, written by Cary Jensen and Loy Anderson and published by McGraw-Hill/Osborne Media Group, that systematically guides a developer through key functionality of Advantage and includes a Companion CD with code samples and a single-user license of Advantage Database Server version 7.0. http://www.extendedsystems.com/ADS/ADS+Book+Promo.htm