The Define tab of the ODBC dBASE Driver Setup dialog box allows you to define the attributes of index files. With the exception of Clipper, the family of databases that includes dBASE and FoxPro uses a multiple index file associated with a particular table (database file). This index file has a .MDX or .CDX extension and is automatically maintained by the driver. Tags within this index can be marked as unique.

Clipper uses single index files that are not automatically associated with a particular table. You can choose to have the driver maintain an index and choose whether or not the index is unique.

To define index file attributes:

  1. Display the ODBC dBASE Driver Setup dialog box.
  2. Click the Define tab.

    The Define tab of the ODBC dBASE Driver Setup dialog box

    On this tab, provide the following information; then, click Apply.

    Table: Type or select the name of the table that contains the database information.

    Multiple Index File: This field displays the name of any multiple index file (with a .CDX extension or .MDX extension) associated with the table you selected. This index file cannot be marked as unique, but tags within it can be.

    Unique Tags: This field displays tags associated with the multiple index file. To mark tags as unique, click each one; each one remains selected until you click it again.

    Single Index Files: The Single Index Files group is active only if you have selected a Clipper table.

    Select the file from the drop-down list to define the attributes of a single index file.

    Maintain Index: Select this check box to associate the specified single index file with the selected table.

    Keep Unique: Select this check box to specify that the single index file is unique.

  3. Click OK or Cancel. If you click OK, the values you have specified become the defaults when you connect to the data source. You can change these defaults by using this procedure to reconfigure your data source. You can override these defaults by connecting to the data source using a connection string with alternate values.