[gnue] r7171 - trunk/gnue-common/src/datasources/drivers/Base

[reinhard]

Author: reinhard
Date: 2005-03-11 12:15:48 -0600 (Fri, 11 Mar 2005)
New Revision: 7171

Modified:
   trunk/gnue-common/src/datasources/drivers/Base/Connection.py
Log:
Added basic placeholders for the requery feature.


Modified: trunk/gnue-common/src/datasources/drivers/Base/Connection.py
===================================================================
--- trunk/gnue-common/src/datasources/drivers/Base/Connection.py        
2005-03-11 17:33:00 UTC (rev 7170)
+++ trunk/gnue-common/src/datasources/drivers/Base/Connection.py        
2005-03-11 18:15:48 UTC (rev 7171)
@@ -145,7 +145,7 @@
 
     @param table: Table name.
     @param oldfields: Fieldname/Value dictionary of fields to find the existing
-      record (aka where-clause)
+      record (aka where-clause).
     @param newfields: Fieldname/Value dictionary of data to change.
     @param recno: Record number to be used in error messages.
     """
@@ -164,7 +164,7 @@
 
     @param table: Table name.
     @param oldfields: Fieldname/Value dictionary of fields to find the existing
-      record (aka where-clause)
+      record (aka where-clause).
     @param recno: Record number to be used in error messages.
     """
 
@@ -173,6 +173,29 @@
     gLeave (8)
 
   # ---------------------------------------------------------------------------
+  # Requery an existing record to reflect changes done by the backend
+  # ---------------------------------------------------------------------------
+
+  def requery (self, table, oldfields, fields):
+    """
+    Requery an existing record to reflect changes done by the backend.
+
+    The returned dictionary is I{not} guaranteed to hold all field given in the
+    fields list (especially for drivers that don't implement this feature).
+    Callers should update() their current field dictionary with the result of
+    this function.
+
+    @param table: Table name.
+    @param oldfields: Fieldname/Value dictionary of fields to find the existing
+      record (aka where-clause).
+    @param fields: List of field names to query.
+    @return: Fieldname/Value dictionary with data fresh from the backend.
+    """
+
+    gEnter (8)
+    gLeave (8, self._requery (table, oldfields, fields))
+
+  # ---------------------------------------------------------------------------
   # Commit pending changes in the backend
   # ---------------------------------------------------------------------------
 
@@ -469,6 +492,25 @@
 
   # ---------------------------------------------------------------------------
 
+  def requery (self, table, oldfields, fields):
+    """
+    Requery an existing record to reflect changes done by the backend (to be
+    implemented by descendants).
+
+    This method can be overwritten by descendants to return current data that
+    might have changed automatically by the backend (e.g. through database
+    triggers or appserver triggers) after an insert or update has been issued.
+
+    @param table: Table name.
+    @param oldfields: Fieldname/Value dictionary of fields to find the existing
+      record (aka where-clause).
+    @param fields: List of field names to query.
+    @return: Fieldname/Value dictionary with data fresh from the backend.
+    """
+    return {}
+
+  # ---------------------------------------------------------------------------
+
   def _commit (self):
     """
     Commit pending changes in the backend (to be implemented by descendants).