Re: Bug in ODBC driver doing UPDATES and DELETES

On Tue, 20 May 2003, Tim Woodall wrote:

>
> When doing an UPDATE or DELETE via ODBC, if no records are affected then
> SQLExecute should return SQL_NO_DATA_FOUND and not SQL_SUCCESS.
>
> I have included two patches below. The first is against RH7.2 latest update
> which is tested. The other is against the latest CVS source and isn't
> tested.
>
>
The following patch to RH9 applies to the version in CVS (with an offset).
This patch has been tested on RH9.

Regards,

Tim.

[tim(at)twlinux psqlodbc]$ patch -p1 <psqlodbc-7.2.5-update.patch
patching file statement.c
Hunk #1 succeeded at 1022 (offset 60 lines).
Hunk #3 succeeded at 1258 (offset 65 lines).
[tim(at)twlinux psqlodbc]$ cat psqlodbc-7.2.5-update.patch
diff -ur psqlodbc-7.2.5.orig/statement.c psqlodbc-7.2.5/statement.c
--- psqlodbc-7.2.5.orig/statement.c 2002-11-29 15:43:50.000000000 +0000
+++ psqlodbc-7.2.5/statement.c 2003-06-16 11:50:32.000000000 +0100
@@ -962,7 +962,14 @@
static char *func = "SC_execute";
ConnectionClass *conn;
APDFields *apdopts;
- char was_ok, was_nonfatal;
+ char was_ok, was_nonfatal, was_rows_affected = 1;
+ /* was_rows_affected is set to 0 iff an UPDATE or DELETE affects
+ * no rows. In this instance the driver should return
+ * SQL_NO_DATA_FOUND and not SQL_SUCCESS.
+ * I'm not sure about the use of char rather than int but this is
+ * consistent with the other was_* variables above.
+ */
+
QResultClass *res = NULL;
Int2 oldstatus,
numcols;
@@ -1082,6 +1089,13 @@
{
was_ok = QR_command_successful(res);
was_nonfatal = QR_command_nonfatal(res);
+ if(res->command &&
+ (strncmp(res->command, "UPDATE", 6) == 0 ||
+ strncmp(res->command, "DELETE", 6) == 0) &&
+ strtoul(res->command + 7, NULL, 0) == 0)
+ {
+ was_rows_affected = 0;
+ }

if (was_ok)
SC_set_errornumber(self, STMT_OK);
@@ -1179,7 +1193,10 @@
}
}
if (SC_get_errornumber(self) == STMT_OK)
- return SQL_SUCCESS;
+ if(was_rows_affected)
+ return SQL_SUCCESS;
+ else
+ return SQL_NO_DATA_FOUND;
else if (SC_get_errornumber(self) == STMT_INFO_ONLY)
return SQL_SUCCESS_WITH_INFO;
else

--
God said, "div D = rho, div B = 0, curl E = - @B/@t, curl H = J + @D/@t,"
and there was light.

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