Deleting an Existing Field 

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       1.      On the maintenance screen of the table, choose the Fields tab page.

       2.      To delete one field from a table, place the cursor on the corresponding line and choose  with the quick info text Delete line.

       3.      Choose  with the quick info text Save.

       4.      Choose  with the quick info text Activate.

If the table in the database already contains data, you must convert the table after deleting existing fields (see Adjusting Database Structures).

If you delete key fields of the table, data may be lost during conversion. If the table contains data records that only differ in the deleted key field, only one of these data records can be loaded back into the table.

You cannot delete a field used as a reference field in another table. In this case you must first remove all the uses of the field as a reference field (see Reference Fields and Reference Tables).

You cannot delete key fields of the table if the table is the check table. In this case, you must first delete the corresponding foreign keys.

To determine all the tables that use the particular table as a check table or reference table, choose  with the quick info text Where-Used List.