Introducing Commands

Summary

In this chapter, you learned the following:

• What an ADO.NET command is and does

• How to create a command

• How to associate a command with a connection

• How to set command text

• When to use the different command execution methods

• How to use ExecuteScalar for queries that return single values

• How to use ExecuteReader to process result sets

• How to use ExecuteNonQuery for DML and DDL

• How to create databases and tables using ExecuteNonQuery

• What command parameters are and how to use them

• How to use commands, specifically OleDbCommand and OdbcCommand, with other data providers

In the next chapter, you’ll look in more depth at data readers, which you created in some of the examples in this chapter with a call to ExecuteReader. Data readers give you the results of a SQL query that returns more than one item of data.