Page 506 - Microsoft Office Excel 2003 Programming Inside Out
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Microsoft Office Excel 2003 Programming Inside Out


                             Caution  If you accidentally delete all the rows from your table, you might be in trouble.
                             Once the rows are deleted, they can’t be undeleted. There isn’t really an Undo function for
                             a database like you find in Excel. Pressing Ctrl+Z will not undo your changes. There are
                             techniques (for example, using transactions) that an advanced database programmer can
                             use to allow you to recover from this type of error, but in general once the rows are deleted,
                             it’s best to assume they’re gone.

                             This example deletes all the rows that have a DateUpdated value that is earlier than 31
                             December 2002.

                             Delete From Customers
                             Where DateUpdated <= ’31-Dec-2002’
                             In this chapter, you learned a little bit about how relational databases such as Microsoft Access
                             and Microsoft SQL Server work. You also learned about the Structured Query Language
                             more commonly referred to as SQL. This language defines statements that allow you to
                             retrieve data from a database (Select), add data to a database (Insert), change data in the data-
                             base (Update), and remove data from the database (Delete).















             Chapter 22

























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             Part 6:  Excel and the Outside World: Collaborating Made Easy
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