tailieunhanh - Sams Teach Yourself Database Programming with Visual C++ 6 in 21 Days phần 3

Các ứng dụng client / server thông thường bao gồm các máy khách (s) đang chạy một ứng dụng Windows, kết nối qua mạng LAN đến một máy chủ cơ sở dữ liệu quan hệ trên một máy chủ mạng - Simpo PDF Merge và Chia Phiên bản máy Chưa đăng ký. Đây là một hệ thống hai cấp (máy khách và máy chủ). | Teach Yourself Database Programming with Visual C 6 in 21 days -- Day 6-Harnessing the Power of Relational Database Servers A Client server applications typically consist of client machine s running a Windows application connected over a SimpooPDFaMergedandaSplitrUnregisteredrVersion - http client and server . Multitier applications typically consist of more than two tiers. The client tier consists of machine s running some kind of a thin client program such as a Web browser or a simple application. There is often a middle tier consisting of machine s running a Web server such as Internet Information Server IIS and or an Object Request Broker ORB such as Microsoft Transaction Server MTS . The server tier typically consists of a server running a relational database. Client tier programs typically communicate with programs on the middle tier which then communicate with the database at the server tier. The clients do not communicate with the database directly only through the middle tier programs. Q When should I use the ADO Recordset AddNew Update and Delete functions instead of stored procedures A For inserting records the ADO Recordset AddNew function can be faster than calling a stored procedure to insert records. For summarizing updating and or deleting records it depends on the number of records you need to work with. If the number of records is small you can get by with pulling the records into a Recordset at the client to process them. If however the number of records isn t small you should consider using a stored procedure called from an ADO Command object. The only caveat for ADO Command objects seems to be that the process of changing parameter values in the Parameters collection can be CPU intensive at the client. Your mileage might vary so write some test code and benchmark the performance for your own applications. Q Can I create Access Queries from within Visual Studio A No the only way to create new Queries in an Access database .