node-oracledb/examples/selectstream.js

81 lines
2.2 KiB
JavaScript

/* Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved. */
/******************************************************************************
*
* You may not use the identified files except in compliance with the Apache
* License, Version 2.0 (the "License.")
*
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
* See the License for the specific language governing permissions and
* limitations under the License.
*
* NAME
* selectstream.js
*
* DESCRIPTION
* Executes a basic query using a Readable Stream.
* Uses Oracle's sample HR schema.
*
* Scripts to create the HR schema can be found at:
* https://github.com/oracle/db-sample-schemas
*
*****************************************************************************/
var oracledb = require('oracledb');
var dbConfig = require('./dbconfig.js');
var rowcount = 0;
oracledb.getConnection(
{
user : dbConfig.user,
password : dbConfig.password,
connectString : dbConfig.connectString
},
function(err, connection) {
if (err) {
console.error(err.message);
return;
}
var stream = connection.queryStream(
'SELECT first_name, last_name FROM employees ORDER BY employee_id',
[], // no binds
{ fetchArraySize: 150 } // internal buffer size for performance tuning
);
stream.on('error', function (error) {
// console.log("stream 'error' event");
console.error(error);
return;
});
stream.on('metadata', function (metadata) {
// console.log("stream 'metadata' event");
console.log(metadata);
});
stream.on('data', function (data) {
// console.log("stream 'data' event");
console.log(data);
rowcount++;
});
stream.on('end', function () {
// console.log("stream 'end' event");
console.log('Rows selected: ' + rowcount);
connection.close(
function(err) {
if (err) {
console.error(err.message);
}
});
});
});