BUG: ALTER TABLE Command Changes Field Type to Picture (130410)

CAUSE

If the word KEY is not supplied when using the ALTER TABLE clause PRIMARY KEY and the column data type and width is not supplied, Visual FoxPro changes the data type of the desired key field to PICTURE rather than generating a syntax error.

RESOLUTION

Provide the word KEY and the column data type and width when using the PRIMARY KEY clause of the ALTER TABLE command, or use the ADD PRIMARY KEY clause of the ALTER TABLE command.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Problem

Issue the following code within the Command window:

   CLOSE ALL
   CLEAR
   CREATE DATABASE mydata     && Creates MYDATA.DBC.
   USE samples\data\orders
   COPY NEXT 10 TO orders2    && Copies the first 10 records from
                              && ORDERS.DBF to a new table ORDERS2.DBF.
   USE                        && Clears ORDERS.DBF from memory.
   ADD TABLE orders2          && Adds orders2 to MYDATA.DBC.
   USE orders2
   DISPLAY STRUCTURE          && Very Important to note that the field
                              && order_id has the character data type.
   CLEAR
   *
   * The next command is used to create a Primary index tag on the
   * field order_id, the syntax should be:
   *
   * ALTER TABLE orders2 ALTER COLUMN order_id C(6) PRIMARY KEY
   * -or-
   * ALTER TABLE orders2 ADD PRIMARY KEY order_id TAG order_id
   *

   ALTER TABLE orders2 ALTER order_id PRIMARY
   DISPLAY STRUCTURE           && Note the data type of order_id is now
                               && Picture.