Limiting rows: LIMIT, TOP and OFFSET FETCH

Most queries in real apps return one page of results, not every row. PostgreSQL and MySQL use LIMIT with OFFSET (how many rows to skip). SQL Server uses TOP (n), or the standard OFFSET ... ROWS FETCH NEXT ... ROWS ONLY form, which needs ORDER BY.

PostgreSQL also accepts the standard FETCH FIRST form. This is the first dialect difference you will meet, where databases spell the same idea differently. Learn to recognise every form, even though you only write your own.

Always pair a limit with ORDER BY, or the rows you get are arbitrary. OFFSET works for early pages but gets slower as the number grows, because the database still reads the rows it skips. The performance stage shows a better method.