node-oracledb/examples/lobplsqltemp.js

128 lines
3.6 KiB
JavaScript

/* Copyright (c) 2016, 2019, 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
* lobtempplsql.js
*
* DESCRIPTION
* Creates a 'temporary CLOB', streams data into it from clobexample.txt, and
* then passes it into a PL/SQL procedure to insert into the database.
*
* Smaller amounts of data can be passed directly to PL/SQL without
* needed a temporary LOB. See lobbinds.js
*
* Create clobexample.txt before running this example.
* Use demo.sql to create the required schema.
*
* This example requires node-oracledb 1.12.1 or later.
*
* This example uses Node 8's async/await syntax.
*
*****************************************************************************/
var fs = require('fs');
var oracledb = require('oracledb');
var dbConfig = require('./dbconfig.js');
var inFileName = 'clobexample.txt'; // the file with text to be inserted into the database
async function run() {
let connection;
try {
connection = await oracledb.getConnection(dbConfig);
// Cleanup anything other than lobinsert1.js demonstration data
await connection.execute(`DELETE FROM mylobs WHERE id > 2`);
// Create an empty Temporary Lob
const tempLob = await connection.createLob(oracledb.CLOB);
// Helper function for loading data to the Temporary Lob
const doStream = new Promise((resolve, reject) => {
let errorHandled = false;
tempLob.on('close', () => {
// console.log("templob.on 'close' event");
});
tempLob.on('error', (err) => {
// console.log("templob.on 'error' event");
if (!errorHandled) {
errorHandled = true;
reject(err);
}
});
tempLob.on('finish', () => {
// console.log("templob.on 'finish' event");
// The data was loaded into the temporary LOB
if (!errorHandled) {
resolve();
}
});
console.log('Reading from ' + inFileName);
var inStream = fs.createReadStream(inFileName);
inStream.on('error', (err) => {
// console.log("inStream.on 'error' event");
if (!errorHandled) {
errorHandled = true;
reject(err);
}
});
inStream.pipe(tempLob); // copies the text to the temporary LOB
});
// Load the data into the Temporary LOB
await doStream;
// Call PL/SQL to insert into the DB
console.log('Calling PL/SQL to insert the temporary LOB into the database');
await connection.execute(
`BEGIN
lobs_in(:id, :c, null);
END;`,
{
id: 3,
c: tempLob // type and direction are optional for IN binds
},
{ autoCommit: true }
);
console.log("Call completed");
// Applications should close LOBs that were created using createLob()
await tempLob.close();
} catch (err) {
console.error(err);
} finally {
if (connection) {
try {
await connection.close();
} catch (err) {
console.error(err);
}
}
}
}
run();