func putBackToSessionPoolExample()

in example/session_pool/table/table_session_pool_example.go [38:108]
66 lines of code
9 McCabe index (conditional complexity)

func putBackToSessionPoolExample() {
	// should create database test_db before executing
	config := &client.PoolConfig{
		Host:     "127.0.0.1",
		Port:     "6667",
		UserName: "root",
		Password: "root",
		Database: "test_db",
	}
	sessionPool := client.NewTableSessionPool(config, 3, 60000, 4000, false)
	defer sessionPool.Close()

	num := 4
	successGetSessionNum := int32(0)
	var wg sync.WaitGroup
	wg.Add(num)
	for i := 0; i < num; i++ {
		dbName := "db" + strconv.Itoa(i)
		go func() {
			defer wg.Done()
			session, err := sessionPool.GetSession()
			if err != nil {
				log.Println("Failed to create database "+dbName+"because ", err)
				return
			}
			atomic.AddInt32(&successGetSessionNum, 1)
			defer func() {
				time.Sleep(6 * time.Second)
				// put back to session pool
				session.Close()
			}()
			checkError(session.ExecuteNonQueryStatement("create database " + dbName))
			checkError(session.ExecuteNonQueryStatement("use " + dbName))
			checkError(session.ExecuteNonQueryStatement("create table table_of_" + dbName + " (tag1 string tag, tag2 string tag, s1 text field, s2 text field)"))
		}()
	}
	wg.Wait()
	log.Println("success num is", successGetSessionNum)

	log.Println("All session's database have been reset.")
	// the using database will automatically reset to session pool's database after the session closed
	wg.Add(5)
	for i := 0; i < 5; i++ {
		go func() {
			defer wg.Done()
			session, err := sessionPool.GetSession()
			if err != nil {
				log.Println("Failed to get session because ", err)
			}
			defer session.Close()
			timeout := int64(3000)
			dataSet, err := session.ExecuteQueryStatement("show tables", &timeout)
			for {
				hasNext, err := dataSet.Next()
				if err != nil {
					log.Fatal(err)
				}
				if !hasNext {
					break
				}
				value, err := dataSet.GetString("TableName")
				if err != nil {
					log.Fatal(err)
				}
				log.Println("table is", value)
			}
			dataSet.Close()
		}()
	}
	wg.Wait()
}