PRB: "Not a Valid Month" Error when Inserting into Oracle Date Fields (230912)

The information in this article applies to:

Microsoft ODBC Driver for Oracle (Build 2.06325) 1.0
Microsoft ODBC for Oracle version 2.5 Build 2.573.2927
Microsoft ODBC for Oracle version 2.5 Build 2.573.4403
Microsoft ODBC for Oracle version 2.5 Build 2.573.6526
Microsoft ODBC for Oracle version 2.5 Build 2.573.7713.2
Microsoft Data Access Components 2.0
Microsoft Data Access Components 2.1
Microsoft Data Access Components 2.5
Microsoft Data Access Components 2.6
Microsoft Data Access Components 2.7

This article was previously published under Q230912

SYMPTOMS

Existing code that successfully inserts records into a Date field in an Oracle table breaks when upgrading the Microsoft ODBC driver for Oracle from version 2.00.XXXX (Msorcl10.dll) to version 2.573.XXXX (Msorcl32.dll).

For example, the following insert statement works with the old version of Microsoft ODBC driver for Oracle (Msorcl10.dll):

.....
sSql = "INSERT INTO DATETEST VALUES ('1988-12-01 10:23:03')"
conn.Execute sSql

However, with the newer version of the Microsoft ODBC driver for Oracle (Msorcl32.dll), the same insert statement gives the following error:

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'
[Microsoft][ODBC driver for Oracle][Oracle]ORA-01843: not a valid month
/Project/xxx.asp, line xx

CAUSE

In the old version of Microsoft ODBC driver for Oracle (Msorcl10.DLL), the ODBC driver does the following when it connects:

ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH:MI:SS'

This explains why an insert of a date field in the following format worked in the previous driver:

'YYYY-MM-DD HH:MI:SS'

With the Microsoft ODBC driver for Oracle (Msorcl32.dll), this feature has been removed. The new driver does not set the date format for Oracle date fields automatically.

RESOLUTION

To allow existing insert statements to work correctly with the new driver, modify your code as follows:

conn.Execute "ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH:MI:SS'"

sSql = "INSERT INTO DATETEST VALUES ('1988-12-01 10:23:03')"

conn.Execute sSql

STATUS

This behavior is by design.

Modification Type:	Major	Last Reviewed:	11/26/2003
Keywords:	kbDatabase kbDriver kbOracle kbprb KB230912