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๐Ÿ’ SQL 77

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: ์นดํ…Œ๊ณ ๋ฆฌ ๋ณ„ ์ƒํ’ˆ ๊ฐœ์ˆ˜ ๊ตฌํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/131529 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT left(PRODUCT_CODE, 2) as CATEGORY, count(*) as COUNT from PRODUCT group by CATEGORY order by CATEGORY asc

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ์ž…์–‘ ์‹œ๊ฐ ๊ตฌํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/59412 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT hour(DATETIME) as HOUR, count(DATETIME) as COUNT from ANIMAL_OUTS where hour(DATETIME) >= 9 and hour(DATETIME) < 20 group by HOUR order by HOUR

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: ์ค‘์„ฑํ™” ์—ฌ๋ถ€ ํŒŒ์•…ํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/59409 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT ANIMAL_ID, NAME, case when SEX_UPON_INTAKE like 'Neutered%' or SEX_UPON_INTAKE like 'Spayed%' then 'O' else 'X' end ์ค‘์„ฑํ™” from ANIMAL_INS order by ANIMAL_ID

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ๊ณ ์–‘์ด์™€ ๊ฐœ๋Š” ๋ช‡ ๋งˆ๋ฆฌ ์žˆ์„๊นŒ

https://school.programmers.co.kr/learn/courses/30/lessons/59040 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT ANIMAL_TYPE, count(*) as count from ANIMAL_INS group by ANIMAL_TYPE order by ANIMAL_TYPE

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: ๊ฐ€๊ฒฉ์ด ์ œ์ผ ๋น„์‹ผ ์‹ํ’ˆ์˜ ์ •๋ณด ์ถœ๋ ฅํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/131115 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT * from FOOD_PRODUCT where PRICE = ( select max(PRICE) from FOOD_PRODUCT )

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: DATETIME์—์„œ DATE๋กœ ํ˜• ๋ณ€ํ™˜

https://school.programmers.co.kr/learn/courses/30/lessons/59414#fn1 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT ANIMAL_ID, NAME, date_format(DATETIME, "%Y-%m-%d") as ๋‚ ์งœ from ANIMAL_INS order by ANIMAL_ID

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: NULL ์ฒ˜๋ฆฌํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/59410 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT ANIMAL_TYPE, ifnull(NAME, 'No name') as NAME, SEX_UPON_INTAKE from ANIMAL_INS

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: ๋™๋ช… ๋™๋ฌผ ์ˆ˜ ์ฐพ๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/59041 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT NAME, count(NAME) as COUNT from ANIMAL_INS group by NAME having count(NAME) >= 2 order by NAME

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit: ์ด๋ฆ„์— el์ด ๋“ค์–ด๊ฐ€๋Š” ๋™๋ฌผ ์ฐพ๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/59047 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT ANIMAL_ID, NAME from ANIMAL_INS where lower(NAME) like '%el%' and ANIMAL_TYPE = 'DOG' order by NAME

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ์กฐ๊ฑด์— ๋ถ€ํ•ฉํ•˜๋Š” ์ค‘๊ณ ๊ฑฐ๋ž˜ ๋Œ“๊ธ€ ์กฐํšŒํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/164673 ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค ์ฝ”๋“œ ์ค‘์‹ฌ์˜ ๊ฐœ๋ฐœ์ž ์ฑ„์šฉ. ์Šคํƒ ๊ธฐ๋ฐ˜์˜ ํฌ์ง€์…˜ ๋งค์นญ. ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค์˜ ๊ฐœ๋ฐœ์ž ๋งž์ถคํ˜• ํ”„๋กœํ•„์„ ๋“ฑ๋กํ•˜๊ณ , ๋‚˜์™€ ๊ธฐ์ˆ  ๊ถํ•ฉ์ด ์ž˜ ๋งž๋Š” ๊ธฐ์—…๋“ค์„ ๋งค์นญ ๋ฐ›์œผ์„ธ์š”. programmers.co.kr -- ์ฝ”๋“œ๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š” SELECT board.TITLE, board.BOARD_ID, reply.REPLY_ID, reply.WRITER_ID, reply.CONTENTS, date_format(reply.CREATED_DATE, "%Y-%m-%d") as CREATED_DATE from USED_GOODS_REPLY as reply join USED_GOODS_BOARD as board on..

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