连接池学习

connectPool/goroutine/readgo.go

@@ -0,0 +1,35 @@
+package goroutine
+
+import (
+	"database/sql"
+	"fmt"
+	"math/rand"
+	"time"
+)
+
+func Dataread(db *sql.DB, donetitle chan struct{}) {
+	// 启动一个长事务（整个循环在一个事务内，而非每次查询一个事务）
+	tx, err := db.Begin()
+	if err != nil {
+		panic(err)
+	}
+	defer tx.Rollback() // 确保退出时回滚（仅为测试）
+
+	// 随机种子（保持不变）
+	rand.Seed(time.Now().UnixNano())
+
+	// 只执行两次查询，方便观察结果
+	for i := 0; i < 2; i++ {
+		select {
+		case <-time.After(2 * time.Second): // 第一次查询后等待2秒，给Datawrite插入时间
+			var count int
+			err = tx.QueryRow("SELECT count(*) FROM article WHERE age > 50  FOR UPDATE ").Scan(&count)
+			if err != nil {
+				panic(err)
+			}
+			fmt.Printf("第%d次查询 count: %d\n", i+1, count)
+		case <-donetitle:
+			return
+		}
+	}
+}

connectPool/goroutine/updatego.go

@@ -0,0 +1,11 @@
+package goroutine
+
+import "database/sql"
+
+func DataUpdate(db *sql.DB) {
+	_, err := db.Begin()
+	if err != nil {
+		panic(err)
+	}
+
+}

connectPool/goroutine/writego.go

@@ -0,0 +1,45 @@
+package goroutine
+
+import (
+	"database/sql"
+	"fmt"
+	"github.com/google/uuid"
+	"math/rand"
+	"strconv"
+	"time"
+)
+
+func Datawrite(db *sql.DB, donetitle chan struct{}) {
+	timetick := time.Tick(1 * time.Second)
+	rand.Seed(time.Now().UnixNano())
+
+	for {
+		select {
+		case <-timetick:
+			uid, error := uuid.NewRandom()
+			if error != nil {
+				panic(error)
+			}
+			tx, err := db.Begin()
+			if err != nil {
+				panic(err)
+			}
+			fmt.Println("开始事务")
+			_, err = tx.Exec(`insert INTO article (uid,content,author,age) values (?,?,?,?)`, uid, "123", "用户"+strconv.Itoa(rand.Intn(1000)), rand.Intn(40)+60)
+			if err != nil {
+				if rbErr := tx.Rollback(); rbErr != nil {
+					panic("回滚失败: " + rbErr.Error())
+				}
+				panic("插入失败: " + err.Error()) // 明确错误类型
+			}
+			err = tx.Commit()
+			if err != nil {
+				panic(err)
+			}
+			fmt.Println("插入数据成功")
+		case <-donetitle:
+			return
+		}
+	}
+
+}

connectPool/pool.go

@@ -0,0 +1,33 @@
+package connectPool
+
+import (
+	"database/sql"
+	"fmt"
+	_ "github.com/go-sql-driver/mysql"
+	"goLearn/connectPool/cursor"
+)
+
+var db *sql.DB
+
+func ConnectPool(donetitle chan struct{}) {
+	dsn := "mayiming:Mydream5654my,@tcp(43.142.81.151:3306)/goLearn?charset-uft8mb4&parseTime=True"
+	db, _ = sql.Open("mysql", dsn)
+
+	err := db.Ping()
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println("数据库连接成功")
+	//for i := 0; i < 20; i++ {
+	//	go goroutine.Datawrite(db, donetitle)
+	//}
+	//go goroutine.Dataread(db, donetitle)
+	cursor.Runcorsor(db)
+}
+
+func DisconnectPool() {
+	err := db.Close()
+	if err != nil {
+		panic(err)
+	}
+}

goroutine/consumer.go

@@ -0,0 +1,26 @@
+package goroutine
+
+import (
+	"fmt"
+	"goLearn/model"
+	"sync"
+)
+
+func NewConsumer(ch chan model.Task, wg *sync.WaitGroup, done chan struct{}, num int, data *model.Data, rwmutex *sync.RWMutex) {
+	defer wg.Done()
+	for {
+		select {
+		case <-ch:
+			rwmutex.RLock()
+			fmt.Printf("消费者%d号处理消息，统计消息总数为：%d\n", num+1, data.Count)
+			fmt.Printf("消费者%d号：当前记录详情如下：\n", num+1)
+			for key, value := range data.Record {
+				fmt.Printf("  键：%d，值：%d\n", key, value)
+			}
+			rwmutex.RUnlock()
+		case <-done:
+			fmt.Printf("消费者%d号退出接收\n", num+1)
+			return
+		}
+	}
+}

goroutine/producer.go

@@ -0,0 +1,44 @@
+package goroutine
+
+import (
+	"fmt"
+	"goLearn/model"
+	"math/rand"
+	"strconv"
+	"sync"
+	"time"
+)
+
+func NewProducer(ch chan model.Task, wg *sync.WaitGroup, done chan struct{}, num int, mutex *sync.Mutex, data *model.Data, rwmutex *sync.RWMutex) {
+	defer wg.Done()
+	timech := time.Tick(1 * time.Second)
+	rand.Seed(time.Now().UnixNano())
+	for {
+		select {
+		case <-timech:
+			fmt.Printf("生产者%d号上锁\n", num+1)
+			randnum := rand.Intn(100)
+			task := model.Task{
+				Id:      strconv.Itoa(randnum),
+				Content: "访问数据库",
+			}
+			mutex.Lock()
+			data.Count += 1
+			mutex.Unlock()
+
+			rwmutex.Lock()
+			data.Record[randnum] += 1
+			rwmutex.Unlock()
+
+			fmt.Printf("生产者%d号注入编号为%s,内容为:%s\n", num+1, task.Id, task.Content)
+			ch <- task
+			fmt.Printf("生产者%d号释放锁\n", num+1)
+
+		case <-done:
+			fmt.Printf("生产者%d号退出任务\n", num+1)
+			return
+		}
+
+	}
+
+}