When switching source engine, the sample effect fired with the previous
engine selected object (e.g. public.sales_orders against MySQL), surfacing
"Table hr.sales_orders doesn't exist". Track which engine the selected
object belongs to and only sample when it matches the active engine, plus
guard against stale responses overwriting newer ones.
Row-count for the browser used an exact count(*) which full-scanned huge
tables (~30s on 24M rows). Use planner/statistics estimates and only run a
time-bounded exact count for small (<=50k) tables.
mo
d05fe403a2