Learning C# 3.0

Summary

• ADO.NET provides classes that allow you to retrieve and manipulate data from databases for use in your code.

• ADO.NET was designed to use a disconnected data architecture, meaning that information is retrieved and stored locally, to diminish use of resource-intensive database connections.

• A database is a structured repository of information, and a relational database is a database that organizes the data into tables.

• The tables in relational databases are further divided into rows, where each row represents a single record, and columns, which represent categories of data.

• The primary key in a table is a column containing values that are unique for each record in that table.

• A foreign key is a column that serves as the primary key for a different table, and helps to create one-to-many relationships among data in separate tables.

• Normalization is the process of removing redundant information from records into separate tables, which reduces complexity and speeds up the retrieval process.

• Constraints set limitations on data to avoid data conflicts and errors.

• SQL is a language commonly used to access and manipulate databases. The fundamental operation in SQL is the query.

• Defining filters with a query allows you to retrieve specific subsets of information.

• Using a join in a query allows you to retrieve data based on membership in more than one table.

• In C#, the DataSet object represents a subset of data retrieved from the database.

• The DataSet object contains a collection called Tables