Connections

These options are on the General tab of the Preferences window (⌘ + ,).¹

Option	What it does
Query time out	How many seconds TablePlus waits for a query to respond before it stops the query. Leave it empty to use the default of 300 seconds.
Keep connection alive	Pings the server every 30 seconds so idle connections aren't closed. On by default.

Query time out

TablePlus stops a query automatically when it hasn't received a response within the time out, so a slow query doesn't hang the workspace forever. Type the number of seconds in the Query time out field and press Return.

Keep connection alive

Some servers, firewalls and SSH tunnels close connections that are idle for a while. With Keep connection alive on, TablePlus pings the server every 30 seconds to keep the connection open.