Oracle Sql 19c Pdf May 2026
-- Approximate distinct count (fast for large tables) SELECT APPROX_COUNT_DISTINCT(customer_id) FROM orders;
-- Approximate distinct count (fast for large tables) SELECT APPROX_COUNT_DISTINCT(customer_id) FROM orders;
-- Approximate distinct count (fast for large tables) SELECT APPROX_COUNT_DISTINCT(customer_id) FROM orders;
매일 아침 국내 투자자가 가장 많이 보는 뉴스레터를 구독하세요