์„œ๋ธŒ์ฟผ๋ฆฌ subquery 1
[SQL] ์„œ๋ธŒ์ฟผ๋ฆฌ subquery

1. ์„œ๋ธŒ์ฟผ๋ฆฌ subquery - SQL ๋ฌธ์„ ์‹คํ–‰ํ•˜๋Š” ๋ฐ ํ•„์š”ํ•œ ๋ฐ์ดํ„ฐ๋ฅผ ์ถ”๊ฐ€๋กœ ์กฐํšŒํ•˜๊ธฐ ์œ„ํ•ด SQL ๋ฌธ ๋‚ด๋ถ€์—์„œ ์‚ฌ์šฉํ•˜๋Š” SELECT ๋ฌธ - ์„œ๋ธŒ์ฟผ๋ฆฌ์˜ ๊ฒฐ๊ณผ ๊ฐ’์„ ์‚ฌ์šฉํ•˜์—ฌ ๊ธฐ๋Šฅ์„ ์ˆ˜ํ–‰ํ•˜๋Š” ์˜์—ญ์€ ๋ฉ”์ธ์ฟผ๋ฆฌ main query ๋ผ๊ณ  ๋ถ€๋ฅธ๋‹ค SELECT ์กฐํšŒํ•  ์นผ๋Ÿผ FROM์กฐํšŒํ•  ํ…Œ์ด๋ธ” WHERE ์กฐ๊ฑด์‹ (SELECT ์กฐํšŒํ•  ์นผ๋Ÿผ FROM์กฐํšŒํ•  ํ…Œ์ด๋ธ” WHERE ์กฐ๊ฑด์‹ ) -- 1. ์ด๋ฆ„์ด JONES์ธ ์‚ฌ์›์˜ ๊ธ‰์—ฌ ์ถœ๋ ฅํ•˜๊ธฐ SELECT SAL FROM EMP WHEREENAME = 'JONES'; -- 2. ๊ธ‰์—ฌ๊ฐ€ 2975๋ณด๋‹ค ๋†’์€ ์‚ฌ์› ์ •๋ณด ์ถœ๋ ฅํ•˜๊ธฐ SELECT * FROM EMP WHERESAL > 2975; -- 3. ์„œ๋ธŒ์ฟผ๋ฆฌ๋กœ JONES๋ณด๋‹ค ๋†’์€ ๊ธ‰์—ฌ ๋ฐ›๋Š” ์‚ฌ์› ์ •๋ณด ์ถœ๋ ฅํ•˜๊ธฐ SELECT * FRO..
ํ”„๋กœ๊ทธ๋ž˜๋ฐ ์–ธ์–ด/DataBase 2021.03.11
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