限制結果數量
ISO / ANSI SQL:
SELECT * FROM TableName FETCH FIRST 20 ROWS ONLY;
MySQL 的; PostgreSQL 的; SQLite 的:
SELECT * FROM TableName LIMIT 20; 
甲骨文:
SELECT Id,
   Col1
FROM (SELECT Id,
           Col1,
           row_number() over (order by Id) RowNumber
      FROM TableName)
WHERE RowNumber <= 20
SQL Server:
SELECT TOP 20 * 
FROM dbo.[Sale]