FIX: Memory leak may occur in Microsoft OLE DB Provider for Oracle when you use the REF CURSOR data type and the LONG data type (815701)



The information in this article applies to:

  • Microsoft Data Access Components 2.7
  • Microsoft Data Access Components 2.8

SYMPTOMS

When you use Microsoft OLE DB Provider for Oracle (MSDAORA) to retrieve data through the REF CURSOR data type, memory leaks may occur. The memory leaks may occur if the data that is retrieved through the REF CURSOR data type is an Oracle LONG data type.

CAUSE

The Microsoft OLE DB provider for Oracle uses special heaps to hold the REF CURSOR data type and the LONG data type. The special heaps let scrolling action occur. Additionally, the special heaps provide storage for lots of data. These special heaps are associated with each recordset that uses the REF CURSOR data type and the LONG data type. A coding error prevents these special heaps from being correctly freed when the recordset object is released and then destroyed.

RESOLUTION

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
 
MDAC 2.7

Date          Time    Version       Size      File name
--------------------------------------------------------------
27-Feb-2003   06:53   2.71.9031.32   221,184   Msdaora.dll 

 
MDAC 2.8

Date          Time    Version       Size      File name
--------------------------------------------------------------
20-Nov-2003  19:55  2.80.1026.0       225,280  Msdaora.dll      
Note For a list of all the hotfixes that are available for MDAC 2.8, click the following article number to view the article in the Microsoft Knowledge Base:

839801 FIX: Hotfixes are available for MDAC 2.8

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

REFERENCES

For additional information about a fix for the problem that is discussed in the following Knowledge Base article that is contained in this hotfix, click the following article number to view the article in the Microsoft Knowledge Base:

322968 CColumnsInfo reference count leak in MSDAORA REF CURSOR when you retrieve data from an Oracle function

For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the standard terminology that is used to describe Microsoft software updates

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.

Modification Type:MajorLast Reviewed:4/7/2006
Keywords:kbQFE KBHotfixServer kbBug kbOracle kbfix KB815701 kbAudDeveloper