## 1. Java应用连接
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class TiDBClient {
public static void main(String[] args) {
try {
// 加载驱动
Class.forName(“com.mysql.cj.jdbc.Driver”);

// 建立连接
String url = “jdbc:mysql://192.168.1.401:4000/fgedudb?useSSL=false&serverTimezone=UTC”;
String user = “fgedu”;
String password = “password”;
Connection conn = DriverManager.getConnection(url, user, password);

// 执行查询
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(“SELECT * FROM fgedu_users”);

// 处理结果
while (rs.next()) {
System.out.println(“ID: ” + rs.getInt(“id”) + “, Name: ” + rs.getString(“name”));
}

// 关闭连接
rs.close();
stmt.close();
conn.close();

} catch (Exception e) {
e.printStackTrace();
}
}
}

## 2. Python应用连接
import pymysql

# 建立连接
conn = pymysql.connect(
host=’192.168.1.401′,
port=4000,
user=’fgedu’,
password=’password’,
database=’fgedudb’,
charset=’utf8mb4′
)

# 创建游标
cursor = conn.cursor()

# 执行查询
cursor.execute(“SELECT * FROM fgedu_users”)

# 获取结果
results = cursor.fetchall()
for row in results:
print(f”ID: {row[0]}, Name: {row[1]}”)

# 关闭连接
cursor.close()
conn.close()

## 3. PHP应用连接
0) {
while ($row = mysqli_fetch_assoc($result)) {
echo “ID: ” . $row[“id”] . “, Name: ” . $row[“name”] . “
“;
}
} else {
echo “0 结果”;
}

// 关闭连接
mysqli_close($conn);
?>

## 1. Spring Boot连接池配置
# application.yml
spring:
datasource:
url: jdbc:mysql://192.168.1.401:4000/fgedudb?useSSL=false&serverTimezone=UTC
username: fgedu
password: password
driver-class-name: com.mysql.cj.jdbc.Driver
hikari:
maximum-pool-size: 20
minimum-idle: 5
idle-timeout: 30000
connection-timeout: 20000
max-lifetime: 1800000

## 2. Node.js连接池配置
const mysql = require(‘mysql2/promise’);

const pool = mysql.createPool({
host: ‘192.168.1.401’,
port: 4000,
user: ‘fgedu’,
password: ‘password’,
database: ‘fgedudb’,
waitForConnections: true,
connectionLimit: 10,
queueLimit: 0
});

// 使用连接池
async function query(sql, params) {
const [rows, fields] = await pool.execute(sql, params);
return rows;
}

// 示例
query(‘SELECT * FROM fgedu_users’).then(rows => {
console.log(rows);
});

## 1. 使用Dumpling导出数据
$ tiup dumpling -h 192.168.1.401 -P 4000 -u fgedu -p password -B fgedudb -o /tidb/backup/fgedudb-$(date
+%Y%m%d)

## 2. 使用Lightning导入数据
$ tiup lightning –pd “192.168.1.101:2379” –backend local –sorted-kv-dir “/tidb/tmp” -d
/tidb/backup/fgedudb-20240101

## 3. 使用BR备份恢复
# 备份
$ tiup br backup full –pd “192.168.1.101:2379” –storage “local:///tidb/backup/br-full-$(date +%Y%m%d)”
–ratelimit 128

# 恢复
$ tiup br restore full –pd “192.168.1.101:2379” –storage “local:///tidb/backup/br-full-20240101”

## 1. 查看集群状态
$ tiup cluster display fgedu-tidb-cluster

## 2. 滚动重启
$ tiup cluster restart fgedu-tidb-cluster –rolling

## 3. 扩容TiKV节点
$ cat > scale-out.yaml << EOF tikv_servers: - host: 192.168.1.204 EOF $ tiup cluster scale-out fgedu-tidb-cluster scale-out.yaml ## 4. 缩容TiKV节点 $ tiup cluster scale-in fgedu-tidb-cluster --node 192.168.1.204:20160 ## 5. 升级集群 $ tiup cluster upgrade fgedu-tidb-cluster v7.5.0

## 1. 检查网络连接
$ ping 192.168.1.401
$ telnet 192.168.1.401 4000

## 2. 检查TiDB服务状态
$ tiup cluster display fgedu-tidb-cluster
$ tiup cluster exec fgedu-tidb-cluster -R tidb –command “systemctl status tidb”

## 3. 检查防火墙
$ firewall-cmd –list-ports
$ firewall-cmd –zone=public –add-port=4000/tcp –permanent
$ firewall-cmd –reload

## 4. 检查用户权限
$ mysql -h 192.168.1.401 -P 4000 -u root -p
mysql> SELECT user, host FROM mysql.user;
mysql> SHOW GRANTS FOR ‘fgedu’@’%’;

## 5. 检查连接数
mysql> SHOW GLOBAL STATUS LIKE ‘Threads%’;
mysql> SHOW GLOBAL VARIABLES LIKE ‘max_connections’;

## 6. 查看TiDB日志
$ tiup cluster logs fgedu-tidb-cluster -R tidb

## 1. 检查网络延迟
$ ping -c 10 192.168.1.401
$ traceroute 192.168.1.401

## 2. 检查TiDB配置
$ tiup cluster config fgedu-tidb-cluster –component tidb

## 3. 调整连接超时设置
# 在tidb.toml中配置
[server]
client-connect-timeout = “10s”

## 4. 检查应用程序连接池设置
# 调整连接超时时间

## 5. 检查系统参数
$ sysctl net.ipv4.tcp_syn_retries
$ sysctl net.ipv4.tcp_fin_timeout