1.drid To configure ：
To configure The default value explain
name The point of configuring this property is , If there are multiple data sources , Monitoring can be distinguished by name . If not configured , Will generate a name , The format is ：“DataSource-” + System.identityHashCode(this)
jdbcUrl Connected to the database url, Different databases are different . for example ： 1）mysql : jdbc:mysql://10.20.153.104:3306/druid 2）oracle : jdbc:oracle:thin:@10.20.149.85:1521:ocnauto
username User name to connect to the database
password Password to connect to the database . If you don't want the password written directly in the configuration file , have access to ConfigFilter. Look here in detail ：https://github.com/alibaba/druid/wiki/%E4%BD%BF%E7%94%A8ConfigFilter
driverClassName according to url Automatic identification This item can be matched or not , If you don't configure druid Will be based on url Automatic identification dbType, Then choose the appropriate driverClassName( It is recommended to configure )
initialSize 0 Number of physical connections established during initialization . Initialization occurs in the display call init Method , Or for the first time getConnection when
maxActive 8 Maximum number of connection pools
maxIdle 8 No longer in use , Configuration has no effect
minIdle Minimum number of connection pools
maxWait Maximum wait time when getting a connection , Unit millisecond . Configured with maxWait after , Fair lock is enabled by default , Concurrency efficiency will decrease , If necessary, it can be configured through useUnfairLock The attribute is true Use unfair locks .
poolPreparedStatements false Whether the cache preparedStatement, That is to say PSCache.PSCache Great improvement in database performance supporting cursors , for instance oracle. stay mysql The next suggestion is to close .
maxOpenPreparedStatements -1 To enable the PSCache, Must be configured greater than 0, When more than 0 when ,poolPreparedStatements Auto trigger changed to true. stay Druid in , No existence Oracle Next PSCache The problem of using too much memory , You can configure this value to be larger , for instance 100
validationQuery Used to check whether the connection is valid sql, The requirement is a query statement . If validationQuery by null,testOnBorrow、testOnReturn、testWhileIdle It doesn't work .
testOnBorrow true Execute on connection request validationQuery Check whether the connection is valid , This configuration will degrade performance .
testOnReturn false Execute... When returning the connection validationQuery Check whether the connection is valid , This configuration will degrade performance
testWhileIdle false Recommended configuration is true, No performance impact , And ensure safety . Check when applying for connection , If the free time is greater than timeBetweenEvictionRunsMillis, perform validationQuery Check whether the connection is valid .
timeBetweenEvictionRunsMillis There are two meanings ： 1) Destroy The thread will detect the connection interval 2) testWhileIdle On the basis of , See in detail testWhileIdle Description of the property
numTestsPerEvictionRun No longer use , One DruidDataSource Only one... Is supported EvictionRun
minEvictableIdleTimeMillis
connectionInitSqls When the physical connection is initialized sql
exceptionSorter according to dbType Automatic identification
filters Property type is string , Configure the extension by alias , Common plug-ins are ： For monitoring statistics filter:stat, It's for the log filter:log4j, defense sql Injected filter:wall
proxyFilters The type is List<com.alibaba.druid.filter.Filter>, If it is configured at the same time filters and proxyFilters, It's a combination relationship , It's not a replacement relationship

Two 、 Open page statistics

Configure the corresponding monitoring :
datasource:
type: com.alibaba.druid.pool.DruidDataSource
url: jdbc:mysql://localhost:3306/dwsurvey?useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true&serverTimezone=Asia/Shanghai
username: root
password: root
driver-class-name: com.mysql.cj.jdbc.Driver
druid:

Number of physical connections established during initialization

  initial-size: 5

Minimum number of connection pools

  min-idle: 5

Maximum number of connection pools

  max-active: 20

Maximum wait time when getting a connection , Unit millisecond

  max-wait: 5000
  #  Condition monitoring 
  filter:
    stat:
    enabled: true
    db-type: mysql
    log-slow-sql: true
    slow-sql-millis: 2000
  #  Monitoring filters 
  web-stat-filter:
    enabled: true
    exclusions:
      - "*.js"
      - "*.gif"
      - "*.jpg"
      - "*.png"
      - "*.css"
      - "*.ico"
      - "/druid/*"
  # druid  Monitoring the page 
  stat-view-servlet:

Whether to turn on monitoring

    enabled: true

Monitoring paths

    url-pattern: /druid/*

Can I reset the data

    reset-enable: false

The login password

    login-password: root

Login name

    login-username: root
  validation-query: "SELECT 1 FROM DUAL "

Visual page address : http://localhost:8080/druid/sql.html

3、 ... and . Single package method ：
If the imported package is single druid You need to configure one for your package bean

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import com.alibaba.druid.wall.WallConfig;
import com.alibaba.druid.wall.WallFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;

@Configuration
public class DruidConfiguration {
    

    
    @Bean
    public ServletRegistrationBean druidServlet() {
    
        // establish servlet Registered entity 
        ServletRegistrationBean<Servlet> bean = new ServletRegistrationBean<>(new StatViewServlet(),"/druid/*");
        // Set up ip White list 
        //servletRegistrationBean.addInitParameter("allow","127.0.0.1");
        // Set up ip The blacklist , If allow And deny Co existing ,deny Prior to the allow
        //servletRegistrationBean.addInitParameter("deny","192.168.0.250");
        // Set up console administration user 
        servletRegistrationBean.addInitParameter("loginUsername","druid");
        servletRegistrationBean.addInitParameter("loginPassword","123456");
        // Can I reset the data 
        servletRegistrationBean.addInitParameter("resetEnable","false");
        bean.setInitParameters(map);
        return bean;

    }

    @Bean
    public FilterRegistrationBean filterRegistrationBean() {
    
        FilterRegistrationBean<Filter> bean = new FilterRegistrationBean<>();
        // Create filters 
        bean.setFilter(new WebStatFilter());
        Map<String,String> map = new HashMap<>();
        // Ignore the form of filtering 
        map.put("exclusions","*.js,*.css,/druid/*");
        // Set filter path 
        bean.setUrlPatterns(Arrays.asList("/*"));
        bean.setInitParameters(map);
        return bean;

    }


    @Bean
    public WallFilter wallFilter(){
    
        WallFilter wallFilter = new WallFilter();
        wallFilter.setConfig(wallConfig());
        return wallFilter;
    }

    @Bean
    public WallConfig wallConfig(){
    
        WallConfig wallConfig = new WallConfig();
        wallConfig.setMultiStatementAllow(true);
        // Allow multiple statements to be executed at one time 
        wallConfig.setNoneBaseStatementAllow(true);
        // Whether other statements other than the above basic statements are allowed 
        wallConfig.setStrictSyntaxCheck(false);
        // Whether strict grammar checking is carried out 
        return wallConfig;
    }

    @Bean(name="dataSource")
    public DataSource dataSource(){
    
        return new DruidDataSource();
    }

    //  Configure things Manager 
    @Bean(name="transactionManager")
    public DataSourceTransactionManager transactionManager(){
    
        return new DataSourceTransactionManager(dataSource());
    }

}

There are some springboot Project startup opens druid The visual interface is normal , But I can't see what is being monitored sql sentence , At this time we are jvm Configure a command when starting ：
-Ddruid.filters=mergeStat -Ddruid.useGlobalDataSourceStat=true
Turn on druid Global monitoring of , That's it ！
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Recommended reading ：
Link to the original text ：https://blog.csdn.net/qq_36364521/article/details/121535424