Delete field
You can use this function to delete optional fields from a table.
It is not possible to delete a mandatory field.
Prerequisites: A database is open.
To run this function: Choose Survey > Survey database > Administration > Delete field, or Database > Database > Administration > Delete field, or Design > Blast design > Database > Administration > Delete field or...
- In the Function Chooser, type DB DELETE FIELD, and press ENTER.
Fields on the Delete fields form
| Field |
Description |
| Table |
The table that contains the field to delete. |
| Field Name |
The field to delete. When you select a table, Field Name is filled with the list of optional fields in that table.
Tip: Press TAB to add an additional row, if you want to delete more than one field.
|
Output
The field or fields you selected are deleted from the database.
| Message |
Description |
Cannot rename table <table_name>. Adding fields failed.
|
In some database drivers, the table must be temporarily renamed so that the new fields can be added or the fields deleted.
If this renaming cannot occur, then this message will appear.
There could be several reasons for this, for example, that the directory specified in the db_specific portion of the .ddb is incorrect.
Make sure this directory is correct, or the functions cannot work.
Another possible reason is that you do not have write permission to the files in the database directory. |
The structure of the data source differs from the structure contained in the .ddb file.
Performing this function may cause instabilities in this database.
No fields will be added or deleted.
Please correct the .ddb and perform this function again.
|
If your data source differs from the .ddb file, then adding and deleting of fields is too dangerous to continue.
This message informs you why the function did not perform anything.
The data source and the .ddb must match exactly.
One way to ensure this is to unload your data to text files, and recreate the database, then load the text files back again. |