oracle

Oracle database driver

Oracle driver for Node.js

A driver to connect to an Oracle database from node.js, leveraging the "Oracle C++ Call Interface" (OCCI) for connectivity. This is most commonly obtained as part of the Oracle Instant Client.

It is known to work with Oracle 10, 11, and 12, and has been mostly tested on Linux, but should also work on OS X and Windows 7+

Basic installation

(See INSTALL.md for complete instructions for your platform.)

Prerequisites:
- Python 2.7 (not v3.x), used by node-gyp
- C++ Compiler toolchain (GCC, Visual Studio or similar)
Download the latest Oracle Instant Client Basic and SDK, and extract to the same directory.
Set environment variables:

OCI_LIB_DIR=/path/to/instant_client OCI_INCLUDE_DIR=/path/to/instant_client/sdk/include OCI_VERSION=<10, 11, or 12> # Integer. Optional, defaults to '11' NLS_LANG=.UTF8 # Optional, but required to support international characters ```

Create symlinks for libclntsh and libocci in the Instant Client directory (see INSTALL.md)
(Linux) Install libaio
Configure the dynamic library path on your platform to include $OCI_LIB_DIR (see INSTALL.md)
npm install oracle to get the latest from npmjs.org

Examples

Basic example

var oracle = require('oracle');
 
var connectData = {
    hostname: "localhost",
    port: 1521,
    database: "xe", // System ID (SID) 
    user: "oracle",
    password: "oracle"
}
 
oracle.connect(connectData, function(err, connection) {
    if (err) { console.log("Error connecting to db:", err); return; }
 
    connection.execute("SELECT systimestamp FROM dual", [], function(err, results) {
        if (err) { console.log("Error executing query:", err); return; }
 
        console.log(results);
        connection.close(); // call only when query is finished executing 
    });
});

Alternative connection using TNS

Replace the connectData object above with one of the following.

Without tnsnames.ora file:

var connString = "(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=xe)))";
var connectData = { "tns": connString, "user": "test", "password": "test" };

With tnsnames.ora file:

DEV =
    (DESCRIPTION =
        (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
        (CONNECT_DATA =
            (SERVER = DEDICATED)
            (SERVICE_NAME = orcl)
        )
    )

var connectData = { "tns": "DEV", "user": "test", "password": "test" };

Connection options

The following options can be set on the connection:

connection.setAutoCommit(true/false);
connection.setPrefetchRowCount(count); Should improve performance with large result sets

Out Params

Following the basic example above, a query using a return parameter looks like this:

    ...
    connection.execute(
        "INSERT INTO person (name) VALUES (:1) RETURNING id INTO :2",
        ['joe ferner', new oracle.OutParam()],
        function(err, results) {
            if ( err ) { ... } 
            // results.updateCount = 1 
            // results.returnParam = the id of the person just inserted 
            connection.close();
        }
    );
    ...

The following OUT Params are supported in Stored Procedures:

OCCIINT
OCCISTRING
OCCIDOUBLE
OCCIFLOAT
OCCICURSOR
OCCICLOB
OCCIDATE
OCCITIMESTAMP
OCCINUMBER
OCCIBLOB

Specify the return type in the OutParam() constructor:

connection.execute("call myProc(:1,:2)", ["nodejs", new oracle.OutParam(oracle.OCCISTRING)], ...

When using OCCISTRING, the size can optionally be specified (default is 200 chars):

connection.execute("call myProc(:1,:2)", ["nodejs", new oracle.OutParam(oracle.OCCISTRING, {size: 1000})], ...

See tests for more examples.

In/Out Params

The following INOUT param types are supported:

OCCIINT
OCCISTRING
OCCIDOUBLE
OCCIFLOAT
OCCINUMBER

INOUT params are used like normal OUT params, with the optional 'in' paramater value being passed in the options object:

connection.execute("call myProc(:1)", [new oracle.OutParam(oracle.OCCIINT, {in: 42})], ...

Validate connection

To validate whether the connection is still established after some time:

if (!connection.isConnected()) {
    // Do something like retire this connection from a pool 
}

Dates

For DATE and TIMESTAMP types, the driver uses the UTC methods from the Javascript Date object. This means the DATE value stored will match the value of new Date().toISOString() on your client machine. Consider this example for a client machine in "GMT-0700":

Table schema:

CREATE TABLE date_test (mydate DATE)

Javascript code:

...
    var date = new Date(2013, 11, 24, 18, 0, 1);  // Client timezone dependent 
    console.log(date.toString());      // Tue Dec 24 2013 18:00:01 GMT-0700 (MST) 
    console.log(date.toISOString());   // 2013-12-25T01:00:01.000Z 
 
    connection.execute(
        "INSERT INTO date_test (mydate) VALUES (:1) " +
            "RETURNING mydate, to_char(mydate, 'YYYY-MM-DD HH24:MI:SS') INTO :2, :3",
        [date, new oracle.OutParam(oracle.OCCIDATE), new oracle.OutParam(oracle.OCCISTRING)],
        function(err, results) {
            console.log(results.returnParam.toString());  // Tue Dec 24 2013 18:00:01 GMT-0700 (MST) 
            console.log(results.returnParam1);            // 2013-12-25 01:00:01 
        }
    );
...

Querying large tables

To query large tables you should use a reader:

reader = connection.reader(sql, args): creates a reader
reader.nextRow(callback): returns the next row through the callback
reader.nextRows(count, callback) returns the next count rows through the callback. count is optional and nextRows uses the prefetch row count when count is omitted. Also, you much check for row.length since the reader will continue returning empty arrays once it exceeds the end of the data set provided by the query.
connection.setPrefetchRowCount(count): configures the prefetch row count for the connection. Prefetching can have a dramatic impact on performance but uses more memory.

Example:

connection.setPrefetchRowCount(50);
var reader = connection.reader("SELECT * FROM auditlogs", []);
 
function doRead(cb) {
    reader.nextRow(function(err, row) {
        if (err) return cb(err);
        if (row) {
            // do something with row 
            console.log("got " + JSON.stringify(row));
            // recurse to read next record 
            return doRead(cb)
        } else {
            // we are done 
            return cb();
        }
    })
}
 
doRead(function(err) {
    if (err) throw err; // or log it 
    console.log("all records processed");
});

Large inserts or updates

To insert or update a large number of records you should use prepared statements rather than individual execute calls on the connection object:

statement = connection.prepare(sql): creates a prepared statement.
statement.execute(args, callback): executes the prepared statement with the values in args. You can call this repeatedly on the same statement.