java - Postgres+JDBC 模板太多客户端已经异常

Question

我正在使用 postgresql，但在从数据库表中获取记录时，我收到此异常致命:抱歉，客户端太多。

下面是连接类:

<context:component-scan base-package="com.trinity" />
      <context:property-placeholder location="classpath:/jdbc.properties" order="1" ignore-unresolvable="true"/>   
      <beans:bean id="dataSourcePOSTGRESQL" class="org.springframework.jdbc.datasource.DriverManagerDataSource">  
        <beans:property name="driverClassName" value="${pg_jdbc.driverClassName}" />
        <beans:property name="url" value="${pg_jdbc.url}" />
        <beans:property name="username" value="${pg_jdbc.username}" />
        <beans:property name="password" value="${pg_jdbc.password}" /> 
    </beans:bean>  

jdbc.propertis

pg_jdbc.driverClassName=org.postgresql.Driver
pg_jdbc1.url1=jdbc:postgresql://localhost:5433/iotdb
pg_jdbc.username=postgres
pg_jdbc.password=track@123

Dao 类:

public List<Map<String, Object>> getAllDevicesNames(Integer companyId) {

    String sql = "select device_configuration_id,device_name,device_id from iot.device_configuration where company_id = ? ";
    List<Map<String, Object>> queryForList = jdbcTemplate.queryForList(sql,new Object[]{companyId});
    return queryForList;

}

Answer 1

之前在我的 postgres.cfg 文件中

max_connections = 100
shared_buffers = 128kb

现在，我更改为

max_connections = 300
shared_buffers = 80MB

工作正常。