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While a SQL query is at the center of every data operation—SELECT, INSERT, UPDATE, or DELETE—you have many ways to get that SQL query defined and executed, and its results examined. You can do almost anything you like as long as you form the SQL correctly and obey the rules of the database you’ve defined.

You shouldn’t regard the examples in these chapters as the dogmatic way to do any one particular task. Their purpose is to present various techniques that you may or may not choose to use in your own pages. Whether you use any one block of code is up to you, but you do at least now know where some code works and where other code doesn’t work.

In the next chapter, we’ll move away from writing code to modify the database and see that the GridView (and its siblings the DetailsView and FormView) allows you to write pages that will automatically propagate the changes to the database, provided that you specify the correct INSERT, UDPATE, and DELETE queries.

In this chapter, we’ve looked at a few topics that will broaden your knowledge and help you build better Web sites. Here, you learned the following:

This chapter completes this book’s coverage of specific techniques for building data-driven Web sites. The next and final chapter provides some guidance on how to put it all together into a well-designed and well-implemented application.

This chapter covered quite a lot of ground. You’ve learned about the following:

Now that you’ve had a taste of how data-driven pages work, we’ll move on to look at how you can connect to the database using code, rather than relying on the SqlDataSource to do all of the work for you.

While a SQL query is at the center of every data operation—SELECT, INSERT, UPDATE, or DELETE—you have many ways to get that SQL query defined and executed, and its results examined. You can do almost anything you like as long as you form the SQL correctly and obey the rules of the database you’ve defined.

You shouldn’t regard the examples in these chapters as the dogmatic way to do any one particular task. Their purpose is to present various techniques that you may or may not choose to use in your own pages. Whether you use any one block of code is up to you, but you do at least now know where some code works and where other code doesn’t work.

In the next chapter, we’ll move away from writing code to modify the database and see that the GridView (and its siblings the DetailsView and FormView) allows you to write pages that will automatically propagate the changes to the database, provided that you specify the correct INSERT, UDPATE, and DELETE queries.

In this chapter, you looked in detail at the DataReader and DataSet objects. These are the two objects most commonly used as the receptacle for query results by data-driven pages.

You learned that the DataReader is a read-only, forward-only, data-provider-specific window on the results of the query sent by a page, and that you can iterate through those results a row at a time using the DataReader’s Read() method. Individual pieces of information can be identified in the current row in a DataReader by name and by index and can be vetted before being used with the DataReader’s HasRows and IsDBNull properties.

In contrast, you saw that the DataSet is data-provider-independent. It’s a container for a group of objects that can describe with some accuracy the table structure and relationships in a database, and because it’s all in memory, the query results stored in a DataSet are read-write and can be accessed in any order. You can either build a complete data structure in code from scratch or Fill() it using a DataAdapter object.

In the next chapter, you’ll begin your exploration of data binding, beginning with inline and list binding.

In this chapter, we’ve looked at a few topics that will broaden your knowledge and help you build better Web sites. Here, you learned the following:

This chapter completes this book’s coverage of specific techniques for building data-driven Web sites. The next and final chapter provides some guidance on how to put it all together into a well-designed and well-implemented application.

In this chapter, you learned how to bind the query results to a table-based Web control such as a GridView, DataList, or Repeater. Unless you tell it otherwise, the GridView will present the results in a preformatted grid, one column per table cell; the DataList and Repeater, on the other hand, must be given a template for each row of information to be displayed.

You learned that you can customize the GridView quite heavily, even when it auto-generates a grid to display query results. You can use SQL to make the data more readable, use styles to make it more attractive, and implement simple sorting and paging functions to improve the way that users can view the results.

In the next chapter, you’ll finish your look at handling the data from a query by exposing it as read-write data. You’ll also learn how to send the changes made to that data back to the database.

While a SQL query is at the center of every data operation—SELECT, INSERT, UPDATE, or DELETE—you have many ways to get that SQL query defined and executed, and its results examined. You can do almost anything you like as long as you form the SQL correctly and obey the rules of the database you’ve defined.

You shouldn’t regard the examples in these chapters as the dogmatic way to do any one particular task. Their purpose is to present various techniques that you may or may not choose to use in your own pages. Whether you use any one block of code is up to you, but you do at least now know where some code works and where other code doesn’t work.

In the next chapter, we’ll move away from writing code to modify the database and see that the GridView (and its siblings the DetailsView and FormView) allows you to write pages that will automatically propagate the changes to the database, provided that you specify the correct INSERT, UDPATE, and DELETE queries.

In this chapter, we’ve looked at a few topics that will broaden your knowledge and help you build better Web sites. Here, you learned the following:

This chapter completes this book’s coverage of specific techniques for building data-driven Web sites. The next and final chapter provides some guidance on how to put it all together into a well-designed and well-implemented application.

This chapter started by looking at the advantages of using stored procedures. Depending on the database server that you’re using, there are several reasons for using stored procedures:

After looking at why you might use stored procedures over direct SQL queries, you then took a step back from the relative complexities of the previous chapters. You created several stored procedures that used the following options you have for passing and returning data to and from stored procedures:

You also saw that there’s very little difference between calling a stored procedure and executing a SQL query. You pass the stored procedure name as the query to execute and tell the Command object or SqlDataSource that you’re executing a stored procedure by specifying StoredProcedure.

We then looked briefly at how to use stored procedures for executing INSERT, UPDATE, and DELETE queries. You saw the definitions of three stored procedures that are replacements for the SQL queries that were introduced in Chapter 8.

In the next chapter, we’l look at the DDL subset of SQL and see what it can do. As you’ll see in the next chapter, you can use SQL to create the entire database, without ever going near a graphical tool.