             }
             
             // Block 1                      Block 2
-            // BEGIN DEFERRED TRANSACTION   BEGIN DEFERRED TRANSACTION
+            // dbPool.read {                dbPool.read {
             // SELECT * FROM items          SELECT * FROM items
             // step                         step
             // >

                }
            }
            
            var i: Int! = nil
            let s1 = DispatchSemaphore(value: 0)
            let s2 = DispatchSemaphore(value: 0)
            try dbPool.write { db in
                try dbPool.readFromCurrentState { db in
                    _ = s1.wait(timeout: .distantFuture)

            // >
            let s5 = DispatchSemaphore(value: 0)
            //                              SELECT COUNT(*) FROM items -> 0
            //                              }
            
            let block1 = { () in
                do {
