Microsoft KB Archive/106279
FIX: SQL SELECT Can Cause Extra Output
2.50 | 2.50
WINDOWS | MS-DOS kbprg kbfixlist kbbuglist The information in this article applies to:
Under certain circumstances, a Structured Query Language (SQL) SELECT command can return extra output.
NOTE: This problem does not occur on all hardware.
Microsoft has confirmed this to be a problem in FoxPro 2.5 for MS-DOS and FoxPro 2.5 for Windows. This problem was corrected in FoxPro 2.5a for MS-DOS and FoxPro 2.5a for Windows.
Steps to Reproduce Problem
Create and run a program with the following code:
* Create A_FILE, B_FILE, and A_B_XREF, which is an x-ref file that * sets up a many-to-many relationship between A_FILE and B_FILE. CREATE TABLE a_file (; a_code C(1), ; a_name C(10) ) CREATE TABLE a_b_xref (; a_code C(1), ; b_code C(1) ) CREATE TABLE b_file (; b_code C(1), ; b_name C(10) ) CLOSE DATABASES * Note that some of the A_CODE values are in * the nonprintable range below ASCII code 32. INSERT INTO a_file VALUES(CHR(29),"A_NAME a29") INSERT INTO a_file VALUES(CHR(30),"A_NAME a30") INSERT INTO a_file VALUES(CHR(31),"A_NAME a31") INSERT INTO a_file VALUES(CHR(32),"A_NAME a32") INSERT INTO a_file VALUES(CHR(33),"A_NAME a33") INSERT INTO a_b_xref VALUES(CHR(30),"1") INSERT INTO a_b_xref VALUES(CHR(31),"1") INSERT INTO a_b_xref VALUES(CHR(29),"2") INSERT INTO a_b_xref VALUES(CHR(32),"2") INSERT INTO a_b_xref VALUES(CHR(33),"2") INSERT INTO b_file VALUES("1","B_NAME 1") INSERT INTO b_file VALUES("2","B_NAME 2") CLOSE DATABASES * Index fields SELECT 0 USE a_file INDEX ON a_code TAG a_code INDEX ON a_name TAG a_name USE SELECT 0 USE a_b_xref INDEX ON a_code TAG a_code INDEX ON b_code TAG b_code USE SELECT 0 USE b_file INDEX ON b_code TAG b_code INDEX ON b_name TAG b_name USE SELECT ; DISTINCT ; a_file.a_name,b_file.b_name ; FROM a_file,a_b_xref,b_file ; WHERE a_file.a_code==a_b_xref.a_code AND ; b_file.b_code==a_b_xref.b_code AND ; b_file.b_name="B_NAME 1"
This program displays a Browse window containing three records. It should display only two records. Additional reference words: FoxDos FoxWin 2.50 buglist2.50 fixlist2.50a KBCategory: kbprg kbfixlist kbbuglist KBSubcategory: FxprgSql Solution Type : kbfix
Last Reviewed: October 14, 1997