Getting Started with the Visual Query Builder GUI :: Visual Query Builder (Database Toolbox)

Database Toolbox

Getting Started with the Visual Query Builder GUI

The Visual Query Builder (VQB) is an easy-to-use graphical user interface (GUI) for exchanging data with your database. With the VQB, you build queries to retrieve data by selecting information from lists rather than by entering MATLAB functions. The VQB retrieves the data from a database and puts it in a MATLAB cell array, structure, or numeric matrix so you can process the data using the MATLAB suite of functions. With the VQB, you can display information retrieved as cell arrays in relational tables, reports, and charts. You can also use the VQB to export data from MATLAB into new rows in your database. Review these key topics when you start using the VQB.

You can use Database Toolbox functions instead of the VQB. See Using the Visual Query Builder Versus Functions for more information.

Before You Start

Before using the Visual Query Builder, set up a data source. This document uses simple examples to demonstrate many of the Visual Query Builder features. These examples use the dbtoolboxdemo data source (tutorial database) for Microsoft Access. Instructions for setting up this or any data source are in Setting Up a Data Source. If you don't have Microsoft Access, you should still be able to follow the examples because they are not complex. If your version of Microsoft Access is different from the one used for the examples, you might get different results. If your results differ, check your version of Access, and compare the table and column names in your databases to those used in the examples.

If you use JDBC drivers on a Windows platform, you cannot use the Visual Query Builder.

Starting the Visual Query Builder

To start the Visual Query Builder interface, type

```
querybuilder
```

at the MATLAB prompt. The Visual Query Builder opens. When you start the VQB, all fields except the Data source are blank. You can also start the interface using the Start menu in the MATLAB desktop.

Visual Query Builder Steps for Retrieving Data with the VQB