<isol>

@ü.li:Listing 1: Tabelle EMP lesen mit Node.js

@li:var oracledb = require('oracledb');

function printEMPResults(err, result) {
  console.log("printEMPResults() start");
  if (err) { console.error(err.message); return; }
  console.log(result.rows);
  console.log("printEMPResults() end");
}

function executeEMPQuery(err, connection) {
  console.log("executeEMPQuery() start");
  if (err) { console.error(err.message); return; }
  connection.execute(
    "SELECT * from EMP where EMPNO = 7844",
    [],
    printEMPResults  // aufrufen, wenn fertig
  );
  console.log("executeEMPQuery() end");
}

console.log("main() start");

oracledb.getConnection(
  {
    user          : "scott",
    password      : "*****",
    connectString : "db-server:db-port/db-service"
  },
  executeEMPQuery  // aufrufen, wenn fertig
); 
console.log("main() end");


@ü.li:Listing 2:Ausführung mit dem Executable <I>node<I>

@li:main() start
main() end
executeEMPQuery() start
executeEMPQuery() end
printEMPResults() start
[ [ 7844,
    'TURNER',
    'SALESMAN',
    7698,
    Tue Sep 08 1981 01:00:00 GMT+0200 (CEST),
    1500,
    0,
    30 ] ]
printEMPResults() end


@ü.li:Listing 3:JSON-Service mit Node.js

@li:var oracledb = require('oracledb');
var express = require('express');

function processEmp(req, res) {
  oracledb.getConnection(
  {
    user          : "scott",
    password      : "*****",
    connectString : "db-server:db-port/db-service"
  },
  function (err, connection) {
    if (err) { console.error(err.message); return; }
    connection.execute(
      "SELECT * from EMP",
      [],
      function (err, result) {
        if (err) { console.error(err.message); return; }
        connection.release(function(err) {});
        res.writeHead(200, {'Content-Type': 'application/json'});
        res.end(JSON.stringify(result.rows));
      }
    );
  });
}

var app =  express();
app.get ("/emp/*", processEmp);

app.listen(9099, function () {});


@ü.li:Listing 4:JSON-Service mit Connection Pool

@li:var oracledb = require('oracledb');
var express = require('express');

var gPool;

function processEmp(req, res) {
  gPool.getConnection(function (err, connection) {
    if (err) { console.error(err.message); return; }
    connection.execute(
      "SELECT * from EMP",
      [],
      function (err, result) {
        if (err) { console.error(err.message); return; }
        connection.release(function(err) {});
        res.writeHead(200, {'Content-Type': 'application/json'});
        res.end(JSON.stringify(result.rows));
      }
    );
  });
}

oracledb.createPool(
  {
    user          : "scott",
    password      : "tiger",
    connectString : "db-server:db-port/db-service"
    poolMin       : 5,
    poolMax       : 10
  },
  function(err, pool) {
    gPool = pool;
    var app =  express();
    app.get ("/emp/*", processEmp);
    app.listen(9099, function () {});
  }
);


@ü.li:Listing 5: SQL Update mit Node.js

@li:  :
  connection.execute(
    "update EMP set SAL = :sal where EMPNO = :empno",
    {sal: 4000, empno: 7839},
    function (err, result) {
      if (err) { console.error(err.message); return; }
      console.log("table EMP updated: " + result.rowsAffected + " rows affected");
      connection.commit(function(err) {});
      connection.release(function(err) {});
    }
  );
  :


@ü.li:Listing 6: Stored Procedures mit Node.js

@li:  :
  connection.execute(
    "begin stored_procedure(:inparam, :outparam); end;",
    {
     inparam:  4000,
     outparam: { dir: oracledb.BIND_OUT, type: oracledb.NUMBER }
    },
    function (err, result) {
      console.log("Ausgabe: " + result.outBinds.outparam);
      connection.release(function(err) {});
    }
  );
  :


@ü.li:Listing 7: Ein Node.js Programm identifiziert sich selbst

@li: gPool.getConnection(function (err, connection) {
    connection.module = "IX Artikel node-oracledb";
    connection.action = "JSON Express Service";
    connection.execute(
      "SELECT * from EMP",
      [],
      function (err, result) { ... }
    );
    connection.module = "";
    connection.action = "";
    connection.release(function(err) {});
  });


@ü.li:Listing 8: Sicht des DBA auf Datenbanksitzungen

@li:SQL> select username, sid, serial#, action, module from v$session where username='SCOTT'

USERNAME    SID ACTION                    MODULE
-------- ------ ------------------------- ------------------------------------------
SCOTT       256 JSON Express Service      IX Artikel node-oracledb
SCOTT        14                           node@sccloud037.de.oracle.com (TNS V1-V3)
SCOTT       267                           node@sccloud037.de.oracle.com (TNS V1-V3)