Sql Node JS Express-Oracle连接池（ORA-24418:无法打开更多会话）

我在Oracle DB模块中遇到问题：

我有一个每小时有300到900次点击的应用程序（通常是大约100个用户）。应用程序在后台有许多$.post请求，用于从数据库检索信息并显示给用户

我最近切换到这个模块，因为它是Oracle自己的（我以前使用过）

以下是我的陈述：

/bin/www

oracledb.createPool(
  {
    user            : 'USER'
    password        : 'PASS',
    connectString   : 'DB:1521/SID:POOLED',
    connectionClass : 'ARBITRARY_NAME',
    poolMin         : 1,
    poolMax         : 50,
    poolTimeout     : 300
  },
  function(err, pool)
  {

  if (err) {
      console.log(err);
  }

  require('../libs/db')(pool);    // Export pool to separate file

 }
)

 /**
 * Database
 */

// AS PER DOCUMENTATION: https://github.com/oracle/node-oracledb/blob/master/examples/dbconfig.js
var dbconfig = require("../libs/dbconfig.js");

oracledb.connectionClass = dbconfig.connectionClass,

oracledb.createPool({
    user:             dbconfig.user,
    password:         dbconfig.password,
    connectString:    dbconfig.connectString,
    poolMax:          44,
    poolMin:          2,
    poolIncrement:    5,
    poolTimeout:      4
}, function(err, pool) {

    if (err) {
      console.log("ERROR: ", new Date(), ": createPool() callback: " + err.message);
      return;
    }

    require('../libs/oracledb.js')(pool);

});

/libs/db.js

module.exports = function(pool) {

// Require oracle module for formatting
var oracledb = require('oracledb');

// Export acquire and query function
module.exports.acquire_and_query = function(sql, params, callback){

  // ACQUIRE connection from pool
  pool.getConnection(function(err, connection){

    // NUMBER OF CONNCETIONS OPEN
    console.log("ORACLE: CONNX OPEN: " + pool.connectionsOpen);

    // NUMBER OF CONNEXTIONS IN USE
    console.log("ORACLE: CONNX IN USE: " + pool.connectionsInUse);
    if (err) {
      console.log(err.message);
      return;
    }

    // Use connection to QUERY db and return JSON object
    connection.execute(sql, params, {maxRows: 1000, isAutoCommit: true, outFormat: oracledb.OBJECT}, function(err, result){

      // Error Handling
      if (err) {
        console.log(err.message);   // Log the error
        return false;               // Return false for our error handling
      }

      // Release the connection back to the pool
      connection.release(function(err) {
        if (err) {
          console.log(err.message);
          return;
        }
      })

      // Return callback with rowset first, out bind paramaters second
      return callback(result.rows, result.outBinds, result.rowsAffected);
    })

  })

}

module.exports = function(pool) {

  ////////////////////////////
  // INSTANTIATE THE DRIVER //
  ////////////////////////////
  var oracledb = require("oracledb");



  //////////////////////
  // GET A CONNECTION //
  //////////////////////
  var doConnect = function(callback) {

    console.log("INFO: Module getConnection() called - attempting to retrieve a connection using the node-oracledb driver");

    pool.getConnection(function(err, connection) {

      // UNABLE TO GET CONNECTION - CALLBACK WITH ERROR
      if (err) { 
        console.log("ERROR: Cannot get a connection: ", err);
        return callback(err);
      }

      // If pool is defined - show connectionsOpen and connectionsInUse
      if (typeof pool !== "undefined") {
        console.log("INFO: Connections open: " + pool.connectionsOpen);
        console.log("INFO: Connections in use: " + pool.connectionsInUse);
      }

      // Else everything looks good
      // Obtain the Oracle Session ID, then return the connection
      doExecute(connection, "SELECT SYS_CONTEXT('userenv', 'sid') AS session_id FROM DUAL", {}, function(err, result) {

        // Something went wrong, releae the connection and return the error
        if (err) {
          console.log("ERROR: Unable to determine Oracle SESSION ID for this transaction: ", err);
          releaseConnection(connection);
          return callback(err);
        }

        // Log the connection ID (we do this to ensure the conncetions are being pooled correctly)
        console.log("INFO: Connection retrieved from the database, SESSION ID: ", result.rows[0]['SESSION_ID']);

        // Return the connection for use in model
        return callback(err, connection);

      });

    });

  }



  /////////////
  // EXECUTE //
  /////////////
  var doExecute = function(connection, sql, params, callback) {

    connection.execute(sql, params, { autoCommit: false, outFormat: oracledb.OBJECT, maxRows:1000 }, function(err, result) {

      // Something went wrong - handle the data and release the connection
      if (err) {
        console.log("ERROR: Unable to execute the SQL: ", err);
        //releaseConnection(connection);
        return callback(err);
      }

      // Return the result to the request initiator
      // console.log("INFO: Result from Database: ", result)
      return callback(err, result);

    });

  }  



  ////////////
  // COMMIT //
  ////////////
  var doCommit = function(connection, callback) {
    connection.commit(function(err) {
      if (err) {
        console.log("ERROR: Unable to COMMIT transaction: ", err);
      }
      return callback(err, connection);
    });
  }



  //////////////
  // ROLLBACK //
  //////////////
  var doRollback = function(connection, callback) {
    connection.rollback(function(err) {
      if (err) {
        console.log("ERROR: Unable to ROLLBACK transaction: ", err);
      }
      return callback(err, connection);
    });
  }



  //////////////////////////
  // RELEASE A CONNECTION //
  //////////////////////////
  var doRelease = function(connection) {

    connection.release(function(err) {
      if (err) {
        console.log("ERROR: Unable to RELEASE the connection: ", err);
      }
      return;
    });

  }



  //////////////////////////////
  // EXPORT THE FUNCTIONALITY //
  //////////////////////////////
  module.exports.doConnect  = doConnect;
  module.exports.doExecute  = doExecute;
  module.exports.doCommit   = doCommit;
  module.exports.doRollback = doRollback;
  module.exports.doRelease  = doRelease;

}

}

这个模块“acquire_and_query”在我们的应用程序中是从中调用的，它具有要执行的SQL及其参数

OracleDB将池连接的最大允许数设置为80（我们没有超过），并且通常看起来非常满意

然而，节点应用程序不断抛出ORA-24418：无法打开更多会话，我不确定如何解决这个问题

---

谢谢。

当到达OCISessionPoolCreate中提供的sessMax参数时，会引发此错误消息

因此，我的第一步是验证数据库会话是否正确关闭

出现此错误消息时，请执行以下三个操作：

1.-（使用sqlplus）显示参数sess

2.-（使用sqlplus） 从v$session中选择用户名、计算机、程序、计数（*） 按用户名、计算机、程序分组 4号命令

3.-在alert.log中验证此事件期间是否存在任何其他ORA-消息

---

您是否执行了这些步骤？（分享您的结果）

已解决-问题：我糟糕的编码

我无意中设置了一个Socket.IO事件来多次更新连接的每个人的视图（而不是查询数据库一次，然后通过套接字发送视图…）

在基于事务的查询中，我甚至更愚蠢地使用for循环（每次运行时插入多个数据）。。。一旦我将其更改为递归模式，它就可以顺利运行了

关于循环和递归模式的好文章：

无论如何，这是我现在使用的（而且效果相当好） 使用节点oracledbv0.6（）和express4（）

bin/www

oracledb.createPool(
  {
    user            : 'USER'
    password        : 'PASS',
    connectString   : 'DB:1521/SID:POOLED',
    connectionClass : 'ARBITRARY_NAME',
    poolMin         : 1,
    poolMax         : 50,
    poolTimeout     : 300
  },
  function(err, pool)
  {

  if (err) {
      console.log(err);
  }

  require('../libs/db')(pool);    // Export pool to separate file

 }
)

 /**
 * Database
 */

// AS PER DOCUMENTATION: https://github.com/oracle/node-oracledb/blob/master/examples/dbconfig.js
var dbconfig = require("../libs/dbconfig.js");

oracledb.connectionClass = dbconfig.connectionClass,

oracledb.createPool({
    user:             dbconfig.user,
    password:         dbconfig.password,
    connectString:    dbconfig.connectString,
    poolMax:          44,
    poolMin:          2,
    poolIncrement:    5,
    poolTimeout:      4
}, function(err, pool) {

    if (err) {
      console.log("ERROR: ", new Date(), ": createPool() callback: " + err.message);
      return;
    }

    require('../libs/oracledb.js')(pool);

});

libs/oracledb.js

module.exports = function(pool) {

// Require oracle module for formatting
var oracledb = require('oracledb');

// Export acquire and query function
module.exports.acquire_and_query = function(sql, params, callback){

  // ACQUIRE connection from pool
  pool.getConnection(function(err, connection){

    // NUMBER OF CONNCETIONS OPEN
    console.log("ORACLE: CONNX OPEN: " + pool.connectionsOpen);

    // NUMBER OF CONNEXTIONS IN USE
    console.log("ORACLE: CONNX IN USE: " + pool.connectionsInUse);
    if (err) {
      console.log(err.message);
      return;
    }

    // Use connection to QUERY db and return JSON object
    connection.execute(sql, params, {maxRows: 1000, isAutoCommit: true, outFormat: oracledb.OBJECT}, function(err, result){

      // Error Handling
      if (err) {
        console.log(err.message);   // Log the error
        return false;               // Return false for our error handling
      }

      // Release the connection back to the pool
      connection.release(function(err) {
        if (err) {
          console.log(err.message);
          return;
        }
      })

      // Return callback with rowset first, out bind paramaters second
      return callback(result.rows, result.outBinds, result.rowsAffected);
    })

  })

}

module.exports = function(pool) {

  ////////////////////////////
  // INSTANTIATE THE DRIVER //
  ////////////////////////////
  var oracledb = require("oracledb");



  //////////////////////
  // GET A CONNECTION //
  //////////////////////
  var doConnect = function(callback) {

    console.log("INFO: Module getConnection() called - attempting to retrieve a connection using the node-oracledb driver");

    pool.getConnection(function(err, connection) {

      // UNABLE TO GET CONNECTION - CALLBACK WITH ERROR
      if (err) { 
        console.log("ERROR: Cannot get a connection: ", err);
        return callback(err);
      }

      // If pool is defined - show connectionsOpen and connectionsInUse
      if (typeof pool !== "undefined") {
        console.log("INFO: Connections open: " + pool.connectionsOpen);
        console.log("INFO: Connections in use: " + pool.connectionsInUse);
      }

      // Else everything looks good
      // Obtain the Oracle Session ID, then return the connection
      doExecute(connection, "SELECT SYS_CONTEXT('userenv', 'sid') AS session_id FROM DUAL", {}, function(err, result) {

        // Something went wrong, releae the connection and return the error
        if (err) {
          console.log("ERROR: Unable to determine Oracle SESSION ID for this transaction: ", err);
          releaseConnection(connection);
          return callback(err);
        }

        // Log the connection ID (we do this to ensure the conncetions are being pooled correctly)
        console.log("INFO: Connection retrieved from the database, SESSION ID: ", result.rows[0]['SESSION_ID']);

        // Return the connection for use in model
        return callback(err, connection);

      });

    });

  }



  /////////////
  // EXECUTE //
  /////////////
  var doExecute = function(connection, sql, params, callback) {

    connection.execute(sql, params, { autoCommit: false, outFormat: oracledb.OBJECT, maxRows:1000 }, function(err, result) {

      // Something went wrong - handle the data and release the connection
      if (err) {
        console.log("ERROR: Unable to execute the SQL: ", err);
        //releaseConnection(connection);
        return callback(err);
      }

      // Return the result to the request initiator
      // console.log("INFO: Result from Database: ", result)
      return callback(err, result);

    });

  }  



  ////////////
  // COMMIT //
  ////////////
  var doCommit = function(connection, callback) {
    connection.commit(function(err) {
      if (err) {
        console.log("ERROR: Unable to COMMIT transaction: ", err);
      }
      return callback(err, connection);
    });
  }



  //////////////
  // ROLLBACK //
  //////////////
  var doRollback = function(connection, callback) {
    connection.rollback(function(err) {
      if (err) {
        console.log("ERROR: Unable to ROLLBACK transaction: ", err);
      }
      return callback(err, connection);
    });
  }



  //////////////////////////
  // RELEASE A CONNECTION //
  //////////////////////////
  var doRelease = function(connection) {

    connection.release(function(err) {
      if (err) {
        console.log("ERROR: Unable to RELEASE the connection: ", err);
      }
      return;
    });

  }



  //////////////////////////////
  // EXPORT THE FUNCTIONALITY //
  //////////////////////////////
  module.exports.doConnect  = doConnect;
  module.exports.doExecute  = doExecute;
  module.exports.doCommit   = doCommit;
  module.exports.doRollback = doRollback;
  module.exports.doRelease  = doRelease;

}

示例用法

//////////////////////////////
// REQUIRE RELEVANT MODULES //
//////////////////////////////
var db          = require("../libs/oracledb.js");
var oracledb    = require('oracledb');
var sql         = "";

///////////////////////////
// RETRIEVE CURRENT DATE //
///////////////////////////
module.exports.getCurDate = function(callback) {

  sql = "SELECT CURRENT_DATE FROM DUAL";
  db.doConnect(function(err, connection){
    console.log("INFO: Database - Retrieving CURRENT_DATE FROM DUAL");
    if (err) {
      console.log("ERROR: Unable to get a connection ");
      return callback(err);
    } else {
      db.doExecute(
        connection, sql
        , {} // PASS BIND PARAMS IN HERE - SEE ORACLEDB DOCS
        , function(err, result) {
            if (err) {
              db.doRelease(connection);     // RELEASE CONNECTION
              return callback(err);                 // ERROR
            } else {
               db.doRelease(connection);     // RELEASE CONNECTION
               return callback(err, result.rows);    // ALL IS GOOD
            }
          }
      );
    }
  });

}

---

也许你有空闲的连接？只是一个建议：您正在

pool.connections的回调中记录
pool.getConnection
。试着把它放在前面，这样在尝试连接之前你会看到连接的数量。谢谢你，罗德里戈-我会试试的。不过出于兴趣，我已经按照Oracle文档中的定义（在示例webapp.js中）对此进行了设置-您认为它可能没有正确地释放连接吗？如果此数据库仅由您的node.js应用程序使用，则可能是这样。或者其他应用程序也使用相同的数据库，比如监控应用程序（比如Lab128）？谢谢Daniel<代码>处理107 250会话57 268 400 400

警报日志中没有任何有趣的内容。