HSQL Database Engine

## In-Memory Applet: QueryTool

## Description

In this demo, all data is kept in memory.
The data will be lost if the program is closed.
The QueryTool and the database are running
inside the internet browser.

## If it does not work

On some browsers (Netscape 4.6?), the version compiled for JDK 1.2 does not work. In the Java Console (Communicator / Extras / Java Console) you will get something like:

# Verifier error org/hsqldb/jdbcConnection.getTypeMap()Ljava/util/Map

This means the class java.util.Map was not found. In JDK 1.1, this class does not exist. When compiled for 1.2, there is a reference to this class required to conform to the JDBC 2.0 interface. This class itself is never used, but the reference is required anyway. It looks like most verifiers have no problems with this, but some have.

The solution for this problem is to recompile (at least the client part) for JDK 1.1. You will need to install JDK 1.1 before you can do this, then see:

Build / How to switch to JDK 1.1