๋ณธ๋ฌธ ๋ฐ”๋กœ๊ฐ€๊ธฐ

๐Ÿ“ฆ ๋ฐ์ดํ„ฐ ๋ฒ ์ด์Šค (DB) ๐Ÿ“ฆ/๐Ÿ…พ ์˜ค๋ผํด DB & SQL27

JOIN๋ฌธ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 /*.. 2021. 2. 10.
ORDER, GROUP BY๋ฌธ - ๋ฌธ์ œ 4 (Scott) 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162-- SCOTT--19) emp ํ…Œ์ด.. 2021. 2. 10.
GROUP BY๋ฌธ - ๋ฌธ์ œ 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 --GROUP BY ํ™œ์šฉ --๋ฌธ์ œ1) EMPLOYEES ํ…Œ์ด๋ธ”์—์„œ ๋ชจ๋“  SALESMAN(SA_MAN)์— ๋Œ€ํ•˜์—ฌ ๊ธ‰์—ฌ์˜ --ํ‰๊ท , ์ตœ๊ณ ์•ก, ์ตœ์ €์•ก, ํ•ฉ๊ณ„๋ฅผ ๊ตฌํ•˜์—ฌ ์ถœ๋ ฅํ•˜์—ฌ๋ผ. SELECT avg(salary), max(salary), min(salary), sum(salary) FROM employees WHERE job_id = 'SA.. 2021. 2. 10.
Power, Trunc, Trim, Round๋“ฑ ๊ฐ์ข… ํ•จ์ˆ˜ํ™œ์šฉ - ๋ฌธ์ œ 2 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394--HR --๋ฌธ์ œ1) EMPLOYEES ํ…Œ์ด๋ธ”์—์„œ King์˜ ์ •๋ณด๋ฅผ ์†Œ๋ฌธ์ž๋กœ ๊ฒ€์ƒ‰ํ•˜๊ณ  ์‚ฌ์›๋ฒˆํ˜ธ,--์„ฑ๋ช…, ๋‹ด๋‹น์—…๋ฌด(์†Œ๋ฌธ์ž๋กœ),๋ถ€์„œ๋ฒˆํ˜ธ๋ฅผ ์ถœ๋ ฅํ•˜๋ผ. SELECT employee_id, last_name, lower(job_id), department_idFROM employeesWHERE LOWER(last_name) = 'king'; --๋ฌธ์ œ2) EMPLOYEES ํ…Œ์ด๋ธ”์—์„œ King์˜ ์ •๋ณด.. 2021. 2. 10.