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diff --git a/src/test/isolation/specs/simple-write-skew.spec b/src/test/isolation/specs/simple-write-skew.spec
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+# Write skew test.
+#
+# This test has two serializable transactions: one which updates all
+# 'apple' rows to 'pear' and one which updates all 'pear' rows to
+# 'apple'.  If these were serialized (run one at a time) either
+# value could be present, but not both.  One must be rolled back to
+# prevent the write skew anomaly.
+#
+# Any overlap between the transactions must cause a serialization failure.
+
+setup
+{
+  CREATE TABLE test (i int PRIMARY KEY, t text);
+  INSERT INTO test VALUES (5, 'apple'), (7, 'pear'), (11, 'banana');
+}
+
+teardown
+{
+  DROP TABLE test;
+}
+
+session s1
+setup { BEGIN ISOLATION LEVEL SERIALIZABLE; }
+step rwx1 { UPDATE test SET t = 'apple' WHERE t = 'pear'; }
+step c1 { COMMIT; }
+
+session s2
+setup { BEGIN ISOLATION LEVEL SERIALIZABLE; }
+step rwx2 { UPDATE test SET t = 'pear' WHERE t = 'apple'}
+step c2 { COMMIT; }