๋ณธ๋ฌธ ๋ฐ”๋กœ๊ฐ€๊ธฐ

๐Ÿ“ฆ ๋ฐ์ดํ„ฐ ๋ฒ ์ด์Šค (DB) ๐Ÿ“ฆ34

SELECT ๋ฌธ - 1 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859/*ํ˜•์‹ :SELECT ( ๊ฐ’, ์ปฌ๋Ÿผ๋ช…(ํ•จ์ˆ˜), ํ•จ์ˆ˜, SUB QUERY)FROM (ํ…Œ์ด๋ธ”๋ช…, SUB QUERY)*/ SELECT 1 FROM DUAL; SELECT * FROM EMP; -- ํ˜„์žฌ ๊ณ„์ •(SCOTT)์˜ ํ…Œ์ด๋ธ”์˜ ์ •๋ณด ๋ชจ๋‘ ๋ช…์„ธํ• ์ˆ˜์žˆ์Œ.SELECT * FROM TAB; SELECT empno, ename, sal FROM EMP; -- ํ•ด๋‹น ํ•ญ๋ชฉ๋งŒ ๋ณผ ์ˆ˜ ์žˆ์Œ. SELECT empno, ename || 300, sal+300 FROM EMP; -- ๋ฌธ์ž์—ด์—” OR || ์—ฐ์‚ฐ์„ ์“ฐ๋ฉด ํ•ฉํ•ด์ง€๊ณ  ์ˆซ์ž์—๋Š” .. 2021. 2. 8.
Standard function (๊ธฐ๋ณธ ํ•จ์ˆ˜) 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104-- Standard Function -- DUAL TABLE : ๊ฐ€์ƒํ…Œ์ด๋ธ” -> ๊ฒฐ๊ณผ ํ™•์ธ์šฉ ํ…Œ์ด๋ธ”SELECT 1 FROM DUAL;SELECT 'A' FROM DUAL;SELECT '๊ฐ€' FROM DUAL;SELECT 23 * 34 FROM DUAL; -- ๋ฌธ์ž ํ•จ์ˆ˜-- CHR( N ) : ASCII ๊ฐ’์„ ๋ฌธ์ž๋กœ ๋ณ€ํ™˜SELECT CHR(65).. 2021. 2. 8.

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