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User Guide

NodeJS

Install the following dependencies from the npm package registry

npm install -S @exasol/exasol-driver-ts ws @types/ws

Connecting to the database:

import { ExasolDriver,ExaWebsocket } from '@exasol/exasol-driver-ts';
import { WebSocket } from 'ws';

const driver = new ExasolDriver((url) => {
      return new WebSocket(url) as ExaWebsocket;
    }, {
        host: "localhost",
        port: 8563,
        user: 'sys',
        password: 'exasol',
        encryption: false,
    });

//connect
await driver.connect();
//execute query
await driver.query("SELECT * FROM EXA_ALL_SCHEMAS");
//close the connection
await driver.close();

Browser

Install the following dependencies from the npm package registry

npm install -S @exasol/exasol-driver-ts

Connecting to the database:

import { ExasolDriver,ExaWebsocket } from '@exasol/exasol-driver-ts';

const driver = new ExasolDriver((url) => {
      return new WebSocket(url) as ExaWebsocket;
    }, {
        host: "localhost",
        port: 8563,
        user: 'sys',
        password: 'exasol',
        encryption: false,
    });

await driver.connect();
await driver.query("SELECT * FROM EXA_ALL_SCHEMAS")
await driver.close();

Further examples

Executing a query using the query method:

//...
//connect
await driver.connect();
//execute query
await driver.query('SELECT * FROM EXA_ALL_SCHEMAS');
//close the connection
await driver.close();

Executing a command using the command method (creating a schema, table and inserting some values):

//...
//connect
await driver.connect();
const schemaName = 'TEST';
//execute commands
await driver.execute('CREATE SCHEMA ' + schemaName);
await driver.execute('CREATE TABLE ' + schemaName + '.TEST_TABLE(x INT)');
await driver.execute('INSERT INTO ' + schemaName + '.TEST_TABLE VALUES (15)');
//close the connection
await driver.close();

Running a query and retrieving the results:

//...
//connect
await driver.connect();
const schemaName = 'TEST';
//run the query
const queryResult = await driver.query('SELECT x FROM ' + schemaName + '.TEST_TABLE');

//print the result
console.log(queryResult.getColumns());
/*
[
  { name: 'X', dataType: { type: 'DECIMAL', precision: 18, scale: 0 } }
]
*/

console.log(queryResult.getRows());
/*
 [ { X: 15 } ]
*/
//close the connection
await driver.close();

Reading out a specific row and column from the result set:

const queryResult = await driver.query('...');
//print out the 0th row, 'X' column value
console.log(queryResult.getRows()[0]['X']);

Supported Driver Properties

Property Value Default Description
host string 'localhost' Host name or ip address.
port number 8563 Port number.
user string Exasol username.
password string Exasol password.
autocommit false=off, true=on true Switch autocommit on or off.
clientName string 'Javascript client' Tell the server the application name.
clientVersion string 1 Tell the server the version of the application.
encryption false=off, true=on true Switch automatic encryption on or off.
fetchSize number, >0 128*1024 Amount of data in kB which should be obtained by Exasol during a fetch. The application can run out of memory if the value is too high.
resultSetMaxRows number Set the max amount of rows in the result set.
schema string Exasol schema name.

Pool

As of version 0.2.0 we now also provide a connection pool called ExasolPool.

NPM packages

Install the following dependencies from the npm package registry:

NodeJS:

npm install --save @exasol/exasol-driver-ts ws @types/ws

Browser:

npm install --save @exasol/exasol-driver-ts

Creating a connection pool:

NodeJs:

import { ExaWebsocket, ExasolPool } from "@exasol/exasol-driver-ts";
import { WebSocket } from 'ws';

const pool = new ExasolPool((url) => {
  return new WebSocket(url) as ExaWebsocket;
}, {
  host: 'localhost',
  port: 8563,
  user: 'sys',
  password: 'exasol',
  encryption: false,
  minimumPoolSize: 1,
  maximumPoolSize: 10,
});

Browser:

import { ExasolDriver,ExaWebsocket } from '@exasol/exasol-driver-ts';

const pool = new ExasolPool((url) => {
  return new WebSocket(url) as ExaWebsocket;
}, {
  host: 'localhost',
  port: 8563,
  user: 'sys',
  password: 'exasol',
  encryption: false,
  minimumPoolSize: 1,
  maximumPoolSize: 10,
});

The configuration is very similar to the ExasolDriver (client). With the added minimumPoolSize and maximumPoolSize options you can specify the minimum and maximum number of active connections in the pool. Defaults are 0 (minimumPoolSize) and 5 (maximumPoolSize).

Runninq a query

const queryResult = await pool.query('SELECT x FROM SCHEMANAME.TABLENAME');

Clearing the pool

Draining and clearing the pool (do this when you don't need the pool anymore or before exiting the application):

await pool.drain();
await pool.clear();

Supported Driver Properties

Property Value Default Description
host string 'localhost' Host name or ip address.
port number 8563 Port number.
user string Exasol username.
password string Exasol password.
autocommit false=off, true=on true Switch autocommit on or off.
clientName string 'Javascript client' Tell the server the application name.
clientVersion string 1 Tell the server the version of the application.
encryption false=off, true=on true Switch automatic encryption on or off.
fetchSize number, >0 128*1024 Amount of data in kB which should be obtained by Exasol during a fetch. The application can run out of memory if the value is too high.
resultSetMaxRows number Set the max amount of rows in the result set.
schema string Exasol schema name.
minimumPoolSize number 0 Minimum amount of active connections.
maximumPoolSize number 5 Maximum amount of active connections.