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Work Areas in Data Sessions

A work area is a numbered region that identifies an open table, its index, and its relationships to other tables in a data session. A data session is a representation of the current dynamic work environment used by a form, form set, or report. When you use data sessions, Visual FoxPro provides a separate environment automatically for each instance of a form or form set. Each data session contains a set of work areas. For more information about data sessions, see How to: Use Data Sessions and How to: View Open Tables in Data Sessions.

In Visual FoxPro, you can open and manipulate tables in 32,767 work areas. Work areas are typically identified in your application using a number or the table alias for the table that is open in the work area. For more information, see How to: Open Tables in Work Areas and How to: Close Tables in Work Areas.

A table alias is a name that refers to a table open in a work area. Using a table alias or name alone specifically identifies the table you want independently from the work area in which the table is open. You can use table aliases in the Visual FoxPro programming language.

When you open a table, Visual FoxPro uses the file name of the table automatically as the default alias. Visual FoxPro also assigns its own default alias to a table automatically under the following circumstances:

  • When you open a table simultaneously in multiple work areas by calling the USE command with the AGAIN clause without specifying an alias when opening the table in each work area.

  • When a conflict exists between aliases.

The default aliases that Visual FoxPro assigns in the first 10 work areas are the work area letters "A" through "J". The aliases assigned in work areas 11 through 32,767 are W11 through W32767. You can use these default aliases to refer to a table open in a work area in the same way as any other default or user-defined alias. For more information, see How to: Create and Use Table Aliases.

See Also

Concepts

Temporary Relationships Between Tables

Other Resources

Managing Tables in Data Sessions

Working with Tables (Visual FoxPro)