Changes between Version 3 and Version 4 of rfc31_ogr_64

Timestamp:

Nov 26, 2010, 8:56:52 AM (13 years ago)

Author:

warmerdam

Comment:

updated with various info.

rfc31_ogr_64

@@ -27 +27 @@
     virtual OGRErr      DeleteFeature( GIntBig nFID );
 }}}
-
 
 == 64bit Fields ==
@@ -78 +77 @@
 As appropriate, existing OGR drivers will be updated to support the new interfaces.  In particular an effort will be made to update the database driver interfaces to support 64bit integer columns for use as feature id, though I am not convinced we should create FID columns as 64bit by default when creating new layers as this may cause problems for other applications.
 
+For prototyping purposes the Shapefile, and PostGIS drivers have been updated to properly support 64bit integer fields.  
+
+Also, all drivers need to be updated to use GIntBig for the FID in the GetFeature() and DeleteFeature() interfaces. 
+
 == Test Suite ==
 
-... it is not yet clear how we would test this change in the test suite ...
+The test suite will be moderately extended to test the new capabilities. 
 
+== Compatibility Issues ==
+
+=== Driver Code Changes ===
+
+ * All drivers implementing DeleteFeature() or GetFeature() will need modest changes. 
+
+ * Most drivers supporting CreateField() likely ought to be extended to support OFTInteger64 as an integer field if nothing else is available (and if bApproxOK is TRUE.
+
+ * Drivers reporting FIDs via Debug statements, printf's or using sprintfs like statements to format them for output will need updates to either cast the FID to long, or to use CPL_FRMT_GIB to format the FID.  Failure to make these changes may result in code crashing.
+
+=== Application Code ===
+
+ * Application code may need to be updated to use GIntBig for FIDs in order to avoid warnings about downcasting.
+
+ * Application code formatting FIDs using printf like facilities may also need to be changed to downcast explicitly or to use CPL_FRMT_GIB.
+
+ * Application code may need to add Integer64 handling in order to utilize wide fields.
+
+=== Behavioral Changes ===
+
+ * Wide integer fields that were previously treated as "real" by the shapefile driver will now be treated as Integer64 which will likely not work with some applications, and translation to other formats will often fail. 
+
+