ADO vs OSQL

OSQL

The osql utility is a Microsoft® Win32® command-prompt utility for ad hoc, interactive execution of Transact-SQL statements and scripts. To use osql, you must understand Transact-SQL. The osql utility is an ODBC client similar to isql, which is based on DB-Library. The osql utility uses the ODBC database application programming interface (API). Both utilities are provided with Microsoft SQL Server version 7.0. The DB-Library API remains at a SQL Server 6.5 level; therefore, applications that depend on DB-Library, such as isql, do not support some SQL Server version 7.0 features. For example, isql cannot access columns defined with the ntext data type and truncates any char, varchar, nchar, or nvarchar columns that are longer than 255 bytes. Except for these limitations in isql, both osql and isql support the same functionality.

ADO Overview

The ActiveX® Data Objects (ADO) programming model represents the best of the existing Microsoft data access programming models. If you are familiar with Data Access Objects (DAO) or Remote Data Objects (RDO), you will recognize the interfaces and will be able to work with them very quickly. You will also notice considerable improvements in the model, and tasks that were awkward in previous models have either been fixed or eliminated from the ADO model.

The ADO objects provide you with the fastest, easiest and most productive means for accessing all kinds of data sources. The ADO model strives to expose everything that the underlying data provider can do, while still adding value by giving you shortcuts for common operations.

ADO is Microsoft\'s strategic, high-level interface to all kinds of data. ADO provides consistent, high-performance access to data, whether you\'re creating a front-end database client or middle-tier business object using an application, tool, language, or even an Internet browser. ADO is the single data interface you need to know for 1- to n-tier client/server and Web-based data-driven solution development.
ADO is designed as an easy-to-use application level interface to Microsoft\'s newest and most powerful data access paradigm, OLE DB. OLE DB provides high-performance access to any data source, including relational and non-relational databases, email and file systems, text and graphics, custom business objects, and more. ADO is implemented with a small footprint, minimal network traffic in key Internet scenarios, and a minimal number of layers between the front-end and data source-all to provide a lightweight, high-performance interface. ADO is easy to use because it is called using a familiar metaphor - the OLE Automation interface, available from just about any tool and language on the market today. And since ADO was designed to combine the best features of, and eventually replace RDO and DAO, it uses similar conventions with simplified semantics to make it easy to learn for today\'s developers.