@Test
    void testDeletePair() {
        String pipelineUuid = UUID.randomUUID().toString();
        String pipelineVersion = UUID.randomUUID().toString();
        RefStreamDefinition refStreamDefinition = new RefStreamDefinition(pipelineUuid, pipelineVersion, 1);

        MapDefinition mapDefinition1 = new MapDefinition(refStreamDefinition, "map1");
        MapDefinition mapDefinition2 = new MapDefinition(refStreamDefinition, "map2");
        MapDefinition mapDefinition3 = new MapDefinition(refStreamDefinition, "map3");

        final Map<UID, MapDefinition> loadedEntries = loadEntries(mapDefinition1, mapDefinition2, mapDefinition3);

        assertThat(mapUidForwardDb.getEntryCount()).isEqualTo(3);
        assertThat(mapUidReverseDb.getEntryCount()).isEqualTo(3);

        lmdbEnv.doWithWriteTxn(writeTxn -> {
            mapDefinitionUIDStore.deletePair(
                    writeTxn,
                    loadedEntries.entrySet().iterator().next().getKey());
        });

        assertThat(mapUidForwardDb.getEntryCount()).isEqualTo(2);
        assertThat(mapUidReverseDb.getEntryCount()).isEqualTo(2);
    }
Noddy test to verify how LMDB copes with different buffer capacities
stroom-pipeline/src/test/java/stroom/pipeline/refdata/store/offheapstore/TestMapDefinitionUIDStore.java