The LIMIT clause is used to specify the maximum number M of results to return to the application. M is computed by an expression that may be a single integer literal, or a single external variable, or any expression which is built from literals and external variables and returns a single non-negative integer.
See Also
Help And Training CommunityGraphQL Content APIUsing the SQL Limit KeywordSalesforce SOQL: Queries and LimitsSemantics
Although it's possible to use limit without an order-by clause, it does not make much sense to do so. This is because without an order-by, results are returned in a random order, so the subset of results returned will be different each time the query is run.
Example 6-41 LIMIT Clause
SELECT * FROM users WHERE age > 30 ORDER BY age LIMIT 5;