Limits

Rows, run time and concurrency.
LimitValue
Rows in any node’s table200,000
Rows returned per node when previewing200
Rows returned per drawn node (chart, map, or a code node’s input)100,000
Rows stored per node in an artifact20,000
Server run time90 s per run
Runs at once (whole Lab)3; a run waits up to 10 s for a turn
Code node run time (browser)120 s

Node results are cached for ten minutes, keyed by the node’s definition and inputs, so running again after a small change only recomputes what changed. The number of problems is not limited.