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Changes between Initial Version and Version 1 of Ticket #30375

-              initial
+              v1
 which can be easily done by overriding BaseOperation.for_update_sql in Postgres DatabaseOperation
+For 1.11
 {{{
 def for_update_sql(self, nowait=False, skip_locked=False):
 …
 }}}
+For 2.2
+{{{
+def for_update_sql(self, nowait=False, skip_locked=False, of=()):
+    """
+    Return the FOR UPDATE SQL clause to lock rows for an update operation.
+    """
+    return 'FOR NO KEY UPDATE%s%s%s' % (
+        ' OF %s' % ', '.join(of) if of else '',
+        ' NOWAIT' if nowait else '',
+        ' SKIP LOCKED' if skip_locked else '',
+    )
+}}}
 Not doing so causes lock contention in our use case.