A query returns ten records. Calling them the first ten assumes an ordering rule that the request may never have supplied.
Define first in relation to something
For a practice table, decide whether first means earliest observation, smallest identifier or another documented choice. In PostgreSQL, the LIMIT documentation warns that a limited subset is unpredictable without an ORDER BY that determines a unique order. LIMIT controls quantity; it does not define which records deserve priority.
Resolve ties deliberately
If several rows share a timestamp, sorting only by that timestamp may leave their relative order undetermined. Add an appropriate tie-breaking key when the task needs a reproducible selection. Record the rule beside the extract, along with the data version or collection time.
This does not turn the selected rows into a random or representative sample. Earliest records may differ systematically from later ones. Explain whether the extract is a debugging example, a preview or evidence for an analysis. The selection rule should fit that purpose rather than inheriting meaning from the order you happened to see.