I built a free desktop SQL client with a live database health dashboard

#database #java #showdev #sql

What is DB Explorer?

DB Explorer is a free, open desktop database client built in Java. It supports
PostgreSQL, MySQL/MariaDB, Oracle, SQL Server, SQLite, and AWS DynamoDB — all from
one tool, with no subscription, no telemetry, and no account required.

What's new in v2.1

The big addition is a live Database Health Dashboard. When you enable it for a
connection, it opens a dedicated background JDBC connection (separate from your
query connection) and polls your database's own system views on a configurable
interval (5–30 seconds).

What it shows:

Active sessions — pulled from pg_stat_activity, SHOW PROCESSLIST, v$session, sys.dm_exec_sessions depending on your DB. Your own session is highlighted.
Server stats — cache hit ratios, commits, rollbacks, wait events
Connection health — green/red indicator, reconnect count, last check timestamp
JVM resources — heap usage bar (amber >70%, red >90%), thread count, GC stats
SQL warnings log — circular buffer of the last 100 warnings

The dashboard is opt-in and disabled by default. Stopping it immediately closes the
background thread and JDBC connection — no background activity unless you turn it on.