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๐Ÿ’ SQL (Programmers) 91

[ํ”„๋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..

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ์ž๋™์ฐจ ๋Œ€์—ฌ ๊ธฐ๋ก์—์„œ ์žฅ๊ธฐ/๋‹จ๊ธฐ ๋Œ€์—ฌ ๊ตฌ๋ถ„ํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/151138 ํ”„๋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 HISTORY_ID, CAR_ID, date_format(START_DATE, '%Y-%m-%d') as START_DATE, date_format(END_DATE, '%Y-%m-%d') as END_DATE, if(datediff(END_DATE, START_DATE)+1>=30, "์žฅ๊ธฐ ๋Œ€์—ฌ", "๋‹จ๊ธฐ ๋Œ€์—ฌ") as RENT_TYPE from CAR_REN..

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ํŠน์ • ์˜ต์…˜์ด ํฌํ•จ๋œ ์ž๋™์ฐจ ๋ฆฌ์ŠคํŠธ ๊ตฌํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/157343 ํ”„๋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 CAR_ID, CAR_TYPE, DAILY_FEE, OPTIONS from CAR_RENTAL_COMPANY_CAR where OPTIONS like "%๋„ค๋น„๊ฒŒ์ด์…˜%" order by CAR_ID desc

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค]SQL ๊ณ ๋“์  Kit: ๊ณผ์ผ๋กœ ๋งŒ๋“  ์•„์ด์Šคํฌ๋ฆผ ๊ณ ๋ฅด๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/133025 ํ”„๋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 FIRST_HALF.FLAVOR from FIRST_HALF join ICECREAM_INFO on FIRST_HALF.FLAVOR = ICECREAM_INFO.FLAVOR where TOTAL_ORDER > 3000 and ICECREAM_INFO.INGREDIENT_TYPE = 'fruit_based' order by TOTAL_ORDER desc

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ํ‰๊ท  ์ผ์ผ ๋Œ€์—ฌ ์š”๊ธˆ ๊ตฌํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/151136 ํ”„๋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 round(avg(DAILY_FEE)) as AVERAGE_FEE from CAR_RENTAL_COMPANY_CAR where CAR_TYPE='SUV';

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ์กฐ๊ฑด์— ๋งž๋Š” ๋„์„œ ๋ฆฌ์ŠคํŠธ ์ถœ๋ ฅํ•˜๊ธฐ

https://school.programmers.co.kr/learn/courses/30/lessons/144853 ํ”„๋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 BOOK_ID, date_format(PUBLISHED_DATE, "%Y-%m-%d") as PUBLISHED_DATE from BOOK where year(PUBLISHED_DATE) = 2021 and CATEGORY = '์ธ๋ฌธ' order by PUBLISHED_DATE asc

[ํ”„๋กœ๊ทธ๋ž˜๋จธ์Šค] SQL ๊ณ ๋“์  Kit : ์ธ๊ธฐ์žˆ๋Š” ์•„์ด์Šคํฌ๋ฆผ

https://school.programmers.co.kr/learn/courses/30/lessons/133024 ํ”„๋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 FLAVOR from FIRST_HALF order by TOTAL_ORDER desc, SHIPMENT_ID asc

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