Microsoft KB Archive/130200

= PRB: Deleted Records are Committed with TABLEUPDATE =

Article ID: 130200

Article Last Modified on 11/17/2003

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APPLIES TO


 * Microsoft Visual FoxPro 3.0 Standard Edition
 * Microsoft Visual FoxPro 5.0 Standard Edition
 * Microsoft Visual FoxPro 6.0 Professional Edition

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This article was previously published under Q130200



SYMPTOMS
A table is opened and table buffering is enabled. During execution of a program, records are added and deleted. When the TABLEUPDATE(.T.) function is used to commit the changes, the records that were appended and then deleted are also committed to the table, and they retain their deleted status. You might expect that records appended and then deleted would not be included in the table, but this is not the case.



CAUSE
Deleting a record does not actually delete information. The delete flag is logical information that determines whether a record needs to be removed at a later date. In the same fashion, deleting a record while buffering is enabled places a flag in the record, so the record (with the delete flag) is committed when a TABLEUPDATE is issued.



RESOLUTION
If you do not want newly added and deleted records to be committed, you can scan the table and search for the appended records. If an appended record has been deleted, use the TABLEREVERT function to discard changes. The following example illustrates this alternative. This example uses local data. CLOSE ALL CLEAR ALL SET MULTILOCKS ON  SET EXCLUSIVE OFF **************************************************  * CREATES A SAMPLE DATABASE AND A SAMPLE TABLE ***************************************************  CREATE DATA test CREATE TABLE Tblbuffer (field1 I, field2 c(10)) INSERT INTO tblbuffer VALUES (1, 'first') INSERT INTO tblbuffer VALUES (2, 'second') INSERT INTO tblbuffer VALUES (3, 'third') ****************************************************  * Sets Optimistic Table Buffering on   ****************************************************

=CURSORSETPROP('buffering',5) ****************************************************  * Appends two blank records and deletes one ****************************************************  APPEND BLANK REPLACE field2 WITH 'ABC' APPEND BLANK REPLACE field2 WITH 'DEF' DELETE ******************************************************  * Updates table. If records have an append status, check * for their deleted flag. If they are deleted, issue a  * TABLEREVERT. *  GO TOP liNextRecord=RECNO DO WHILE liNextRecord!=0 IF DELETED AND "4" $ STR(GETFLDSTATE(0)) =TABLEREVERT ELSE =TABLEUPDATE ENDIF liCurrRecno=RECNO liNextRecord=GETNEXTMODIFIED(liCurrRecno) IF !EOF SKIP ENDIF ENDDO

** BROWSE the table to see the problem BROWSE



STATUS
This behavior is by design.

