MDB Reader

JavaScript library to read data from Access databases.

Installation

npm install mdb-reader

or

yarn add mdb-reader

Compatibility

Node / JavaScript

• Node 18 and 20
• Works in the browser with buffer (Example)

Access Database versions

• Access 97 (Jet 3)
• Access 2000, XP and 2003 (Jet 4)
• Access 2010 (ACE14)
• Access 2013 (ACE15)
• Access 2016 (ACE16)
• Access 2019 (ACE17)

Encryption

• Jet
• Office Agile
• Office RC4 Crypto API

Dependencies

To decrypt databases, this library requires a few dependencies:

• browserify-aes: Only imported when running in browser
• create-hash: Only imported when running in browser
• fast-xml-parser

Usage

import { readFileSync } from "fs";
import MDBReader from "mdb-reader";

const buffer = readFileSync("database.mdb");
const reader = new MDBReader(buffer);

reader.getTableNames(); // ['Cats', 'Dogs', 'Cars']

const table = reader.getTable("Cats");
table.getColumnNames(); // ['id', 'name', 'color']
table.getData(); // [{id: 5, name: 'Ashley', color: 'black'}, ...]

API

MDBReader

class MDBReader {
    /**
     * @param buffer Buffer of the database.
     */
    constructor(
        buffer: Buffer,
        options?: {
            password?: string;
        }
    );

    /**
     * Date when the database was created
     */
    getCreationDate(): Date | null;

    /**
     * Database password
     */
    getPassword(): string | null;

    /**
     * Default sort order
     */
    getDefaultSortOrder(): Readonly<SortOrder>;

    /**
     * Returns an array of table names.
     *
     * @param normalTables Includes user tables.
     * @param systemTables Includes system tables.
     * @param linkedTables Includes linked tables.
     */
    getTableNames({
        normalTables,
        systemTables,
        linkedTables,
    }?: {
        normalTables: boolean;
        systemTables: boolean;
        linkedTables: boolean;
    }): string[];

    /**
     * Returns a table by its name.
     *
     * @param name Name of the table. Case sensitive.
     */
    getTable(name: string): Table;
}

Table

class Table {

    /**
     * Name of the table
     */
    readonly name: string,

    /**
     * Number of rows.
     */
    readonly rowCount: number;

    /**
     * Number of columns.
     */
    readonly columnCount: number;

    /**
     * Returns an ordered array of all column definitions.
     */
    getColumns(): Column[];

    /**
     * Returns a column definition by its name.
     *
     * @param name Name of the column. Case sensitive.
     */
    getColumn(name: string): Column;

    /**
     * Returns an ordered array of all column names.
     */
    getColumnNames(): string[];

    /**
     * Returns data from the table.
     *
     * @param columns Columns to be returned. Defaults to all columns.
     * @param rowOffset Index of the first row to be returned. 0-based. Defaults to 0.
     * @param rowLimit Maximum number of rows to be returned. Defaults to Infinity.
     */
    getData<TRow extends {
        [column in TColumn]: Value;
        TColumn extends string = string;
    }>(options?: {
        columns?: ReadonlyArray<TColumn>;
        rowOffset?: number;
        rowLimit?: number;
    }): TRow[];
}

Column

interface Column {
    /**
     * Name of the table
     */
    name: string;

    /**
     * Type of the table
     */
    type: ColumnType;
    size: number;

    fixedLength: boolean;
    nullable: boolean;
    autoLong: boolean;
    autoUUID: boolean;

    /**
     * Only exists if type = 'numeric'
     */
    precision?: number;

    /**
     * Only exists if type = 'numeric'
     */
    scale?: number;
}

Data Types

The data types returned by Table.getData() depends on the column type. Null values are always returned as null.

Column Type	JavaScript Type
bigint	bigint
binary	Buffer
boolean	boolean
byte	number
complex	number
currency	string
datetime	Date
datetimeextended	string
double	number
float	number
integer	number
long	number
memo	string
numeric	string
ole	Buffer
repid	string
text	string

Development

Build

To build the library, first install the dependencies, then run npm run build for a single build or npm run watch for automatic rebuilds.

npm install
npm run build

Tests

To run the tests, first install the dependencies, then run npm test. Watch mode can be started with npm test -- --watch.

npm install
npm test

Resources

MDB Tool

GitHub

Set of applications to read and write Access files, written in C. Main source of knowledge about the file structure and algorithms to extract data from it.

Jackcess

Jackcess

Java library to read and write Access files. It inspired the interface of this library. The databases used for testing are copied from the repository.

The unofficial MDB Guide

Tech Specs for the JET format used by Access 1997-2010

License

MIT