Office 2007 Professional Key Composite keys in Web

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A composite key consists of more than one field in an index. They are often used to ensure uniqueness across fields in a record. You can use unique multiple field indexes to define a set of columns that uniquely identify a row so as to prevent users from entering in the same record twice. Composite keys (multiple field indexes) are not supported on Access Services; however you can use Data Macros to get the same behavior. Let’s look at a common example for a school registration systems.We have a Students and a Classes table: The Enrollment table keeps track of which students are in which classes. The Student and Class fields are lookups to the Students and Classes tables respectively. Using Indexes, we can prevent a Student from being in the same class multiple times by creating a new index for the Enrollment table,Office 2007 Professional Key, like below. This will throw an error every time you try to add a student to a class they are already in. In Access 2010,Office 2007 Activation Key, we can get the same functionality using data macros. In the BeforeChange event, just set up a LookupRecord block to look through the Enrollment table to see if the student is already enrolled in the class. If so,Microsoft Office 2007 Key, it will throw an error to the user; otherwise the student will be added to the class. Here is the user experience of the app running:Hopefully,Microsoft Office Pro Plus, this article is helpful as you migrate your apps to the Web. Enjoy,Microsoft Office 2010 Pro!Kerry Westphal <div