WITH

jijiยท2023๋…„ 12์›” 20์ผ
0

DataBase

๋ชฉ๋ก ๋ณด๊ธฐ
13/14

๐Ÿ”ฅ WITH์ ˆ

  • WITH์ ˆ์€ SQl์—์„œ ์„œ๋ธŒ์ฟผ๋ฆฌ์˜ ๊ฒฐ๊ณผ๋ฅผ ์ž„์‹œ๋กœ ์ •์˜ํ•œ๋‹ค.
  • ์ž„์‹œ ํ…Œ์ด๋ธ”์ด๋‚˜ ๋ทฐ์ฒ˜๋Ÿผ ์ž‘๋™
  • ์ฟผ๋ฆฌ ๋‚ด ์žฌ์‚ฌ์šฉ์ด ๊ฐ€๋Šฅํ•˜๋‹ค
-- ์„œ๋ธŒ์ฟผ๋ฆฌ ์ •์˜
WITH 
    subquery_name AS (
        SELECT column1, column2, ...
        FROM table_name
        WHERE conditions
    ),
    another_subquery AS (
        SELECT ...
        FROM ...
        WHERE ...
    )
   
-- ๋ฉ”์ธ์ฟผ๋ฆฌ
SELECT 
    *
FROM 
    main_table
JOIN 
    subquery_name ON ...
WHERE 
    ...

1. ์„œ๋ธŒ์ฟผ๋ฆฌ ์ •์˜:

WITH ํ‚ค์›Œ๋“œ ์ž„์‹œ๋กœ ์ƒ์„ฑ๋  ์„œ๋ธŒ์ฟผ๋ฆฌ์˜ ์ด๋ฆ„ + AS ํ•„์š”ํ•œ ์ปฌ๋Ÿผ๋“ค์„ ์ •์˜

  • ์‹ค์ œ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ํ…Œ์ด๋ธ”์ด๋‚˜ ๋ทฐ๊ฐ€ ์•„๋‹ˆ๋ผ, ์„œ๋ธŒ์ฟผ๋ฆฌ์˜ ์ด๋ฆ„๊ณผ ๊ทธ ๊ฒฐ๊ณผ๋ฅผ ์ •์˜ํ•˜๋Š” ๊ตฌ๊ฐ„

2. ๋ฉ”์ธ ์ฟผ๋ฆฌ:

์„œ๋ธŒ์ฟผ๋ฆฌ๋ฅผ ํ™œ์šฉํ•˜์—ฌ ๋ฐ์ดํ„ฐ๋ฅผ ๊ฐ€์ ธ์˜ค๋Š” ๋ฉ”์ธ ์ฟผ๋ฆฌ ๋ถ€๋ถ„์ž…๋‹ˆ๋‹ค.
WITH ์ ˆ์—์„œ ์ •์˜ํ•œ ์ด๋ฆ„์„ ํ†ตํ•ด ์„œ๋ธŒ์ฟผ๋ฆฌ์˜ ๊ฒฐ๊ณผ๋ฅผ ์‚ฌ์šฉํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

0๊ฐœ์˜ ๋Œ“๊ธ€