Q193079: FIX: "Syntax Error" with EVAL of ALL or LTRIM in SELECT-SQL

Article: Q193079
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a
Operating System(s): 
Keyword(s): 
Last Modified: 12-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a 
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SYMPTOMS
========

If you issue a SELECT SQL statement that contains a WHERE clause comparing a
field value to an expression, which involves an ALLTRIM() or LTRIM() function
that is passed to the EVALUATE() function, if the trim function trims a leading
space or spaces the following error occurs when the SELECT statement is
processed:

  Syntax error.

RESOLUTION
==========

As a workaround, trim the leading space or spaces by using STRTRAN() rather than
ALLTRIM() or LTRIM().

The following example demonstrates the workaround:

     SELECT *, .t. FROM temp_table ;
        WHERE temp_table.cUsageTL = EVALUATE(STRTRAN("lcService" ;
        + (" 91")," ","")) ;
        INTO CURSOR Temp4

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug has been corrected in Visual FoxPro 6.0.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Run the following code from a program (.PRG) file:

        CLOSE DATABASES ALL
        SET SAFETY OFF

        * Create table and index.
        CREATE table temp_table (cBTN c(2), cUsageTl c(10))
        INDEX on cUsageTl tag cUsageTl

        SET SAFETY ON

        * Insert some records.
        FOR lnj = 1 to 10
           INSERT into temp_table (cBTN, cUsageTl) values ("91", "Sp800/W")
           INSERT into temp_table (cBTN, cUsageTl) values ("91", "Sp800/X")
           INSERT into temp_table (cBTN, cUsageTl) values ("91", "Sp800/Y")
        ENDFOR

        * Initialize variables to Evaluate.
        lcService91="Sp800/W"
        lcService92="Sp800/X"
        lcService93="Sp800/Y"

        * Issue SELECT with trailing, no and leading space.
        SELECT *, .t. FROM temp_table WHERE temp_table.cUsageTl = ;
           EVALUATE("lcService"+ALLTRIM("91 ")) ;
           INTO CURSOR Temp2

        SELECT *, .t. FROM temp_table WHERE temp_table.cUsageTl = ;
           EVALUATE("lcService"+ALLTRIM("92")) ;
           INTO CURSOR Temp3

        * It fails with the leading space.
        SELECT *, .t. FROM temp_table WHERE temp_table.cUsageTl = ;
           EVALUATE("lcService"+ALLTRIM(" 93")) ;
           INTO CURSOR Temp4

In Visual FoxPro 5.0, the third select fails with a "Syntax error". This works
without error in Visual FoxPro 6.0.

Demonstration of Workaround
---------------------------

Replace the third select statement in the preceding program example with the
following code:

     SELECT *, .t. FROM temp_table ;
        WHERE temp_table.cUsageTL = EVALUATE(STRTRAN("lcService" ;
        + (" 91")," ","")) ;
        INTO CURSOR Temp4

RESULTS: After running the program, no error occurs, and the STRTRAN() function
trims the leading space.

REFERENCES
==========

(c) Microsoft Corporation 1998. All Rights Reserved. Contributions by Jim
Saunders, Microsoft Corporation


Additional query words: kbVFp500abug kbVFp600fix kbSQL

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP500a
Version           : WINDOWS:5.0,5.0a
Issue type        : kbbug
Solution Type     : kbfix

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