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๐Ÿ“ ๋ฐฐ์šฐ๊ณ  ์ตํžˆ๊ธฐ +/ORACLE

(38)[oracle]3์ผ์ฐจ: NVL(), NVL2(), COALESCE()/ ์ปฌ๋Ÿผ๊ณผ ์ปฌ๋Ÿผ์˜ ์—ฐ๊ฒฐ(๊ฒฐํ•ฉ)/ ๋ฌธ์ž์—ด ์•ˆ ํ™‘๋”ฐ์˜ดํ‘œ/ UPPER(), LOWER(), INITCAP()/ TO_DATE()/ BETWEEN โ“ AND โ“‘/ IN, =ANY/ LIKE '%''_'/ ESCAPE/ COMMIT, ROLLBACK

by ์ข…์ด๋นจ๋Œ€ 2023. 10. 19.
TOP

๋ชฉ์ฐจ

    1. 23.10.18(๋ชฉ)

    1. 20231019_01_scott.sql

    SELECT USER
    FROM DUAL;
    --==>> SCOTT
    
    /* 20231018-7-๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ 20๋ฒˆ ๋ถ€์„œ์— ๊ทผ๋ฌดํ•˜์ง€ ์•Š๋Š” ์ง์›๋“ค์˜
    --    ์‚ฌ์›๋ช…, ์ง์ข…๋ช…, ๋ถ€์„œ๋ฒˆํ˜ธ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    DESC TBL_EMP;
    
    SELECT EMPNO "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", DEPTNO "๋ถ€์„œ๋ฒˆํ˜ธ"
    FROM TBL_EMP
    WHERE 20๋ฒˆ ๋ถ€์„œ์— ๊ทผ๋ฌดํ•˜์ง€ ์•Š๋Š”;
    
    SELECT EMPNO "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", DEPTNO "๋ถ€์„œ๋ฒˆํ˜ธ"
    FROM TBL_EMP
    WHERE ๋ถ€์„œ๋ฒˆํ˜ธ๊ฐ€ 20๋ฒˆ์ด ์•„๋‹ˆ๋‹ค;
    
    SELECT EMPNO "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", DEPTNO "๋ถ€์„œ๋ฒˆํ˜ธ"
    FROM TBL_EMP
    WHERE DEPTNO != 20;
        
    SELECT EMPNO "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", DEPTNO "๋ถ€์„œ๋ฒˆํ˜ธ"
    FROM TBL_EMP
    WHERE DEPTNO <> 20;
    
    SELECT EMPNO "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", DEPTNO "๋ถ€์„œ๋ฒˆํ˜ธ"
    FROM TBL_EMP
    WHERE DEPTNO ^= 20;
    --==>>
    /*
    7499	SALESMAN	30
    7521	SALESMAN	30
    7654	SALESMAN	30
    7698	MANAGER	30
    7782	MANAGER	10
    7839	PRESIDENT	10
    7844	SALESMAN	30
    7900	CLERK	30
    7934	CLERK	10
    */
    
    /* 1-๋ฌธ์ œ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ์ปค๋ฏธ์…˜์ด NULL ์ด ์•„๋‹Œ ์ง์›๋“ค์˜
    --  ์‚ฌ์›๋ช…, ์ง์ข…๋ช…, ๊ธ‰์—ฌ, ์ปค๋ฏธ์…˜ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    WHERE COMM IS NOT NULL;
    /* 1-๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    WHERE ์ปค๋ฏธ์…˜์ด NULL์ด ์•„๋‹Œ;
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    WHERE COMM์ด NULL์ด ์•„๋‹Œ;
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    --WHERE COMM != NULL;
    --WHERE COMM <> NULL;
    WHERE COMM ^= NULL;
    ==>> ์กฐํšŒ๊ฒฐ๊ณผ ์—†์Œ
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    WHERE COMM IS NULL;     -- && -> AND    || -> OR    ! -> NOT
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    WHERE COMM IS NOT NULL;
    /*
    ALLEN	SALESMAN	1600	300
    WARD	SALESMAN	1250	500
    MARTIN	SALESMAN	1250	1400
    TURNER	SALESMAN	1500	0
    */
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
    FROM TBL_EMP
    WHERE NOT COMM IS NULL;
    --** NOT์„ ์•ž์œผ๋กœ ์˜ฎ๊ฒจ๋„ ๋…ผ๋ฆฌ์ ์œผ๋กœ ๊ฐ€๋Šฅ
    --==>>
    /*
    ALLEN	SALESMAN	1600	300
    WARD	SALESMAN	1250	500
    MARTIN	SALESMAN	1250	1400
    TURNER	SALESMAN	1500	0
    */
    
    /* 2-๋ฌธ์ œ & ๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ๋ชจ๋“  ์‚ฌ์›๋“ค์˜                           --** ๋ชจ๋“ ์‚ฌ์›๋“ค:  WHERE ์กฐ๊ฑด์ด ์—†๋‹ค๋Š” ๋œป
    --    ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ๊ธ‰์—ฌ, ์ปค๋ฏธ์…˜, ์—ฐ๋ด‰ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    --    ๋‹จ, ๊ธ‰์—ฌ(SAL)๋Š” ๋งค์›” ์ง€๊ธ‰ํ•œ๋‹ค.
    --    ๋˜ํ•œ, ์ˆ˜๋‹น(COMM)์€ ์—ฐ 1ํšŒ ์ง€๊ธ‰ํ•˜๋ฉฐ, ์—ฐ๋ด‰ ๋‚ด์—ญ์— ํฌํ•จ๋œ๋‹ค.
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜", ๊ธ‰์—ฌ*12+์—ฐ๋ด‰ 
    FROM TBL_EMP;
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜", (SAL*12)+COMM "๊ธ‰์—ฌ" 
    FROM TBL_EMP;
    --==>> ๊ฐ’์ด ๋‚˜์˜ค๊ธดํ•˜๋‚˜,  COMM ์ด NULL ์ธ ๊ฒฝ์šฐ ๊ฐ’์ด NULL๋กœ ๋‚˜์˜ค๋Š” ๋ฌธ์ œ๊ฐ€ ๋„์ถœ
    
    --โ—‹ NVL()
    --์ฒซ ๋ฒˆ์งธ ํŒŒ๋ผ๋ฏธํ„ฐ ๊ฐ’์ด NULL ์ด๋ฉด, ๋‘ ๋ฒˆ์งธ ํŒŒ๋ผ๋ฏธํ„ฐ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•œ๋‹ค.
    --์ฒซ ๋ฒˆ์งธ ํŒŒ๋ผ๋ฏธํ„ฐ ์•–์ด NULL ์ด ์•„๋‹ˆ๋ฉด, ๊ทธ ๊ฐ’์„ ๊ทธ๋Œ€๋กœ ๋ฐ˜ํ™˜ํ•œ๋‹ค.
    SELECT NULL "COL1", NVL(NULL,10) "COL2", NVL(5, 10) "COL3"
    FROM DUAL;
    --==>> (NULL)	10	5
    
    SELECT ENAME "์‚ฌ์›๋ช…", COMM "์ˆ˜๋‹น"
    FROM TBL_EMP;
    
    SELECT ENAME "์‚ฌ์›๋ช…", NVL(COMM,1234) "์ˆ˜๋‹น"
    FROM TBL_EMP;
    
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
            , SAL*12+NVL(COMM,0) "์—ฐ๋ด‰" 
    FROM TBL_EMP;
    /*
    7369	SMITH	800	    (NULL)	9600
    7499	ALLEN	1600	300	    19500
    7521	WARD	1250	500	    15500
    7566	JONES	2975	(NULL)	35700
    7654	MARTIN	1250	1400	16400
    7698	BLAKE	2850	(NULL)	34200
    7782	CLARK	2450	(NULL)	29400
    7788	SCOTT	3000	(NULL)	36000
    7839	KING	5000	(NULL)	60000
    7844	TURNER	1500	0	    18000
    7876	ADAMS	1100	(NULL)	13200
    7900	JAMES	950		11400
    7902	FORD	3000	(NULL)	36000
    7934	MILLER	1300	(NULL)	15600
    */
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
            , NVL(SAL*12*COMM, SAL*12) "์—ฐ๋ด‰" 
    FROM TBL_EMP;
    
    --โ—‹ NVL2()
    --> ์ฒซ ๋ฒˆ์งธ ํŒŒ๋ผ๋ฏธํ„ฐ ๊ฐ’์ด NULL ์ด ์•„๋‹Œ ๊ฒฝ์šฐ, ๋‘ ๋ฒˆ์งธ ํŒŒ๋ผ๋ฏธํ„ฐ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•˜๊ณ 
    --  ์ฒซ ๋ฒˆ์งธ ํŒŒ๋ผ๋ฏธํ„ฐ ๊ฐ’์ด NULL ์ธ ๊ฒฝ์šฐ, ์„ธ ๋ฒˆ์งธ ํŒŒ๋ฆฌ๋ฏธํ„ฐ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•œ๋‹ค.
    SELECT ENAME "์‚ฌ์›๋ช…", NVL2(COMM, '์ฒญ๊ธฐ์˜ฌ๋ ค', '๋ฐฑ๊ธฐ์˜ฌ๋ ค')"์ˆ˜๋‹นํ™•์ธ"
    FROM TBL_EMP;
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
            , NVL2(COMM, SAL*12+COMM, SAL*12) "์—ฐ๋ด‰"
    FROM TBL_EMP;
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
            , SAL*12+NVL2(COMM, COMM, 0) "์—ฐ๋ด‰"
    FROM TBL_EMP;
    
    --โ—‹ COALESCE()
    --> ๋งค๊ฐœ๋ณ€์ˆ˜ ์ œํ•œ์ด ์—†๋Š” ํ˜•ํƒœ๋กœ ์ธ์ง€ํ•˜๊ณ  ํ™œ์šฉํ•œ๋‹ค.
    --  ๋งจ ์•ž์— ์žˆ๋Š” ๋งค๊ฐœ๋ณ€์ˆ˜๋ถ€ํ„ฐ ์ฐจ๋ก€๋กœ NULL ์ธ์ง€ ์•„๋‹Œ์ง€ ํ™•์ธํ•˜์—ฌ
    --  NULL ์ด ์•„๋‹Œ ๊ฒฝ์šฐ ๊ทธ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•˜๊ณ ,
    --  NULL ์ธ ๊ฒฝ์šฐ์—๋Š” ๊ทธ ๋‹ค์Œ ๋งค๊ฐœ๋ณ€์ˆ˜์˜ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•œ๋‹ค.
    --  NVL()์ด๋‚˜ NVL2() ์™€ ๋น„๊ตํ–ˆ์„ ๋•Œ
    --  ๋ชจ~~~~ ๋“  ๊ฒฝ์šฐ์˜ ์ˆ˜๋ฅผ ๊ณ ๋ คํ•  ์ˆ˜ ์žˆ๋‹ค๋Š” ํŠน์ง•์„ ๊ฐ–๋Š”๋‹ค.
    
    SELECT NULL"COL1"
        , COALESCE(NULL, NULL, NULL, 40) "COL2"
        , COALESCE(NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 100) "COL3"
        , COALESCE(NULL, NULL, 30, NULL, NULL, 60) "COL4"
        , COALESCE(10, NULL, NULL, NULL, NULL, 60) "COL5"
    FROM DUAL;
    --==>> 	40	100	30	10
    
    INSERT INTO TBL_EMP(EMPNO, ENAME, JOB, MGR, HIREDATE, DEPTNO)
    VALUES(8000, '๊น€๋‘˜๋ฆฌ', 'SALESMAN', 7369, SYSDATE, 10);
    --==>> 1 ํ–‰ ์ด(๊ฐ€) ์‚ฝ์ž…๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    INSERT INTO TBL_EMP(EMPNO, ENAME, JOB, MGR, HIREDATE, DEPTNO,COMM)
    VALUES(8001, '๋ฐ•๋˜์น˜', 'SALSESMAN',7369, SYSDATE, 10, 10);
    --==>> 1 ํ–‰ ์ด(๊ฐ€) ์‚ฝ์ž…๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    --โ—‹ ํ™•์ธ
    SELECT *
    FROM TBL_EMP;
    /*
    8000	๊น€๋‘˜๋ฆฌ	SALESMAN	7369	2023-10-19	(NULL)	(NULL)	10
    8001	๋ฐ•๋˜์น˜	SALSESMAN	7369	2023-10-19	(NULL)	10	    10
    */
    
    --โ—‹ ์ปค๋ฐ‹
    COMMIT;
    --==> ์ปค๋ฐ‹ ์™„๋ฃŒ.
    
    /* 3-๋ฌธ์ œ & ๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ๋ชจ๋“  ์‚ฌ์›๋“ค์˜
    --    ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ๊ธ‰์—ฌ, ์ปค๋ฏธ์…˜, ์—ฐ๋ด‰ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    --    ๋‹จ, ๊ธ‰์—ฌ(SAL)๋Š” ๋งค์›” ์ง€๊ธ‰ํ•œ๋‹ค.
    --    ๋˜ํ•œ, ์ˆ˜๋‹น(COMM)์€ ์—ฐ 1ํšŒ ์ง€๊ธ‰ํ•˜๋ฉฐ, ์—ฐ๋ด‰ ๋‚ด์—ญ์— ํฌํ•จ๋œ๋‹ค.
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", SAL "๊ธ‰์—ฌ", COMM "์ปค๋ฏธ์…˜"
            ,COALESCE(SAL*12+COMM, SAL*12, COMM, 0) "์—ฐ๋ด‰"
    FROM TBL_EMP;
    
    --โ€ป ๋‚ ์งœ์— ๋Œ€ํ•œ ์„ธ์…˜ ์„ค์ • ๋ณ€๊ฒฝ
    ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH:MI:SS';
    --==>> Session์ด(๊ฐ€) ๋ณ€๊ฒฝ๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    --โ—‹ ์ปฌ๋Ÿผ๊ณผ ์ปฌ๋Ÿผ์˜ ์—ฐ๊ฒฐ(๊ฒฐํ•ฉ)
    SELECT 1,2
    FROM DUAL;
    --==>> 1	2
    
    SELECT 1+2
    FROM DUAL;
    --** ์˜จ์ „ํžˆ ๊ฒฐํ•ฉ์ด๋ผ๊ณ  ๋ณด๊ธฐ ์–ด๋ ค์›€, ํ•˜๋‚˜์˜ ์ปฌ๋Ÿผ์— ์—ฐ์‚ฐ์„ ๋„ฃ์€ ๊ฒƒ
    
    SELECT '๊น€๋‘˜๋ฆฌ', '๋ฐ•๋˜์น˜'
    FROM DUAL;
    
    SELECT '๊น€๋‘˜๋ฆฌ' + '๋ฐ•๋˜์น˜'
    FROM DUAL;
    --=>> ์—๋Ÿฌ๋ฐœ์ƒ(ORA-01722: invalid number)
    
    SELECT '๊น€๋‘˜๋ฆฌ' || '๋ฐ•๋˜์น˜'
    FROM DUAL;
    --==>> ๊น€๋‘˜๋ฆฌ๋ฐ•๋˜์น˜
    
    SELECT ENAME, JOB
    FROM TBL_EMP;
    
    SELECT ENAME || JOB
    FROM TBL_EMP;
    --==>>
    /*
    SMITHCLERK
    ALLENSALESMAN
    WARDSALESMAN
    JONESMANAGER
    MARTINSALESMAN
    BLAKEMANAGER
    CLARKMANAGER
    SCOTTANALYST
    KINGPRESIDENT
    TURNERSALESMAN
    ADAMSCLERK
    JAMESCLERK
    FORDANALYST
    MILLERCLERK
    ๊น€๋‘˜๋ฆฌSALESMAN
    ๋ฐ•๋˜์น˜SALSESMAN
    */
    
    SELECT 'ํ–‰๋ณต์ด๋Š”', SYSDATE, '์— ์—ฐ๋ด‰ ', 500, ' ์–ต์„ ์›ํ•œ๋‹ค.'
    FROM DUAL;
    --==>> ํ–‰๋ณต์ด๋Š”	2023-10-19 10:41:18	์— ์—ฐ๋ด‰ 	500	 ์–ต์„ ์›ํ•œ๋‹ค.
    --     -------- ------------------- -------     ---- -------------
    --      ๋ฌธ์žํƒ€์ž… ๋‚ ์งœํƒ€์ž…           ๋ฌธ์žํƒ€์ž…  ์ˆซ์žํƒ€์ž… ๋ฌธ์žํƒ€์ž…
    
    --โ—‹ ํ˜„์žฌ ๋‚ ์งœ ๋ฐ ์‹œ๊ฐ„์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜
    SELECT SYSDATE, CURRENT_DATE, LOCALTIMESTAMP
    FROM DUAL;
    --==>> 2023-10-19 10:43:40	2023-10-19 10:43:40	23/10/19 10:43:40.000000000
    
    SELECT 'ํ–‰๋ณต์ด๋Š”' || SYSDATE || '์— ์—ฐ๋ด‰ ' || 500 || ' ์–ต์„ ์›ํ•œ๋‹ค.'
    FROM DUAL;
    --==>> ํ–‰๋ณต์ด๋Š”2023-10-19 10:44:55์— ์—ฐ๋ด‰ 500 ์–ต์„ ์›ํ•œ๋‹ค.
    
    --โ€ป ์˜ค๋ผํด์—์„œ๋Š” ๋ฌธ์ž ํƒ€์ž…์˜ ํ˜•ํƒœ๋กœ ํ˜•(TYPE)์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ๋ณ„๋„์˜ ๊ณผ์ • ์—†์ด
    --    ใ€Ž||ใ€ ๋งŒ ์‚ฝ์ž…ํ•ด ์ฃผ๋ฉด ๊ฐ„๋‹จํžˆ ์ปฌ๋Ÿฝ๊ณผ ์ปฌ๋Ÿฝ(์„œ๋กœ ๋‹ค๋ฅธ ์ข…๋ฅ˜์˜ ๋ฐ์ดํ„ฐ)์„
    --    ๊ฒฐํ•ฉํ•˜๋Š” ๊ฒƒ์ด ๊ฐ€๋Šฅํ•˜๋‹ค.
    --    cf) MSSQL ์—์„œ๋Š” ๋ชจ๋“  ๋ฐ์ดํ„ฐ๋ฅผ ๋ฌธ์ž์—ด๋กœ CONVERT ํ•ด์•ผ ํ•œ๋‹ค.
    
    โ€ป ๋‚ ์งœ ๊ด€๋ จ ์„ธ์…˜ ์„ค์ • ๋ณ€๊ฒฝ
    ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD';
    --==>>Session์ด(๊ฐ€) ๋ณ€๊ฒฝ๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    
    /* 4-๋ฌธ์ œ & ๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์˜ ๋ฐ์ดํ„ฐ๋ฅผ ํ™œ์šฉํ•˜์—ฌ
    --    ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๊ฒฐ๊ณผ๋ฅผ ์–ป์„ ์ˆ˜ ์žˆ๋„๋ก ์ฟผ๋ฆฌ๋ฌธ์„ ๊ตฌ์„ฑํ•œ๋‹ค.
    --    <SMITH์˜ ํ˜„์žฌ ์—ฐ๋ด‰์€ 9600์ธ๋ฐ ํฌ๋ง ์—ฐ๋ด‰์€ 19200์ด๋‹ค.
    --     SLLEN์˜ ํ˜„์žฌ ์—ฐ๋ด‰์€ 19500์ธ๋ฐ ํฌ๋ง ์—ฐ๋ด‰์€ 390000์ด๋‹ค.
    --     
    --     ๋ฐ•๋˜์น˜์˜ ํ˜„์žฌ ์—ฐ๋ด‰์€ 10์ธ๋ฐ ํฌ๋ง ์—ฐ๋ด‰์€ 20์ด๋‹ค.> 
    --    ๋‹จ, ๋ ˆ์ฝ”๋“œ๋งˆ๋‹ค ์œ„์™€ ๊ฐ™์€ ๋‚ด์šฉ์ด ํ•œ ์ปฌ๋Ÿผ์— ๋ชจ๋‘ ์กฐํšŒ๋˜ ์ˆ˜ ์žˆ๋„๋ก ์ฒ˜๋ฆฌํ•œ๋‹ค.
    SELECT *
    FROM TBL_EMP;
    
    SELECT ENAME || '์˜ ํ˜„์žฌ ์—ฐ๋ด‰์€ ' || COALESCE(SAL*12+COMM,SAL*12,COMM,0) || 
                  '์ธ๋ฐ ํฌ๋ง ์—ฐ๋ด‰์€ ' || COALESCE(SAL*12+COMM,SAL*12,COMM,0)*2 || '์ด๋‹ค.'
    FROM TBL_EMP;
    
    /* 5-๋ฌธ์ œ & ๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์˜ ๋ฐ์ดํ„ฐ๋ฅผ ํ™œ์šฉํ•˜์—ฌ
    --    ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๊ฒฐ๊ณผ๋ฅผ ์–ป์„ ์ˆ˜ ์žˆ๋„๋ก ์ฟผ๋ฆฌ๋ฌธ์„ ๊ตฌ์„ฑํ•œ๋‹ค.
    --    <SMITH's ์ž…์‚ฌ์ผ์€ 1980-12-17์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 800์ด๋‹ค.
    --     ALLEN's ์ž…์‚ฌ์ผ์€ 1981-02-20์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1600์ด๋‹ค.
    --     
    --     ๋ฐ•๋˜์น˜'s ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 0์ด๋‹ค.>
    --    ๋‹จ, ๋ ˆ์ฝ”๋“œ๋งˆ๋‹ค ์œ„์™€ ๊ฐ™์€ ๋‚ด์šฉ์ด ํ•œ ์ปฌ๋Ÿผ์— ๋ชจ๋‘ ์กฐํšŒ๋  ์ˆ˜ ์žˆ๋„๋ก ์ฒ˜๋ฆฌํ•œ๋‹ค.
    SELECT ENAME || '''s ์ž…์‚ฌ์ผ์€ ' || SYSDATE || '์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” ' || NVL(SAL,0) || '์ด๋‹ค.' 
    FROM TBL_EMP;
    
    --โ€ป ๋ฌธ์ž์—ด์„ ๋‚˜ํƒ€๋‚ด๋Š” ํ™‘๋”ฐ์˜ดํ‘œ ์‚ฌ์ด์—์„œ(์‹œ์ž‘๊ณผ ๋)
    --    ํ™‘๋”ฐ์˜ดํ‘œ ๋‘ ๊ฐœ๊ฐ ํ™‘๋”ฐ์˜ดํ‘œ ํ•˜๋‚˜(์–ดํผ์ŠคํŠธ๋กœํ”ผ)๋ฅผ ์˜๋ฏธํ•œ๋‹ค.
    --    ํ™‘๋”ฐ์˜ดํ‘œ ํ•˜๋‚˜(<'>)๋Š” ๋ฌธ์ž์—ด์˜ ์‹œ์ž‘์„ ๋‚˜ํƒ€๋‚ด๊ณ ,
    --    ํ™‘๋”ฐ์˜ดํ‘œ ๋‘๊ฐœ(<''>)๋Š” ๋ฌธ์ž์—ด ์˜์—ญ ์•ˆ์—์„œ ์–ดํผ์ŠคํŠธ๋กœํ”ผ๋ฅผ ๋‚˜ํƒ€๋‚ด๋ฉฐ
    --    ๋‹ค์‹œ ๋งˆ์ง€๋ง‰์— ๋“ฑ์žฅํ•˜๋Š” ํ™‘๋”ฐ์˜ดํ‘œ ํ•˜๋‚˜(<'>)๋Š” ๋ฌธ์ž์—ด ์˜์—ญ์˜ ์ข…๋ฃŒ๋ฅผ ์˜๋ฏธํ•˜๊ฒŒ ๋˜๋Š” ๊ฒƒ์ด๋‹ค.
        
    --==>>
    /*
    SMITH's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 800์ด๋‹ค.
    ALLEN's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1600์ด๋‹ค.
    WARD's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1250์ด๋‹ค.
    JONES's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 2975์ด๋‹ค.
    MARTIN's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1250์ด๋‹ค.
    BLAKE's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 2850์ด๋‹ค.
    CLARK's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 2450์ด๋‹ค.
    SCOTT's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 3000์ด๋‹ค.
    KING's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 5000์ด๋‹ค.
    TURNER's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1500์ด๋‹ค.
    ADAMS's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1100์ด๋‹ค.
    JAMES's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 950์ด๋‹ค.
    FORD's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 3000์ด๋‹ค.
    MILLER's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 1300์ด๋‹ค.
    ๊น€๋‘˜๋ฆฌ's ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 0์ด๋‹ค.
    ๋ฐ•๋˜์น˜'s ์ž…์‚ฌ์ผ์€ 2023-10-19์ด๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ธ‰์—ฌ๋Š” 0์ด๋‹ค.
    */
    
    SELECT *
    FROM TBL_EMP
    WHERE JOB = 'SALESMAN';
    --==>>
    /*
    7499	ALLEN	SALESMAN	7698	1981-02-20	1600	300	    30
    7521	WARD	SALESMAN	7698	1981-02-22	1250	500	    30
    7654	MARTIN	SALESMAN	7698	1981-09-28	1250	1400	30
    7844	TURNER	SALESMAN	7698	1981-09-08	1500	0	    30
    8000	๊น€๋‘˜๋ฆฌ	SALESMAN	7369	2023-10-19	(NULL)	(NULL)	10
    */
    
    SELECT *
    FROM TBL_EMP
    WHERE JOB = 'salesman';
    --==>> ์กฐํšŒ๊ฒฐ๊ณผ ์—†์Œ
    
    SELECT *
    FROM TBL_EMP
    WHERE JOB = 'Salesman';
    --==>> ์กฐํšŒ๊ฒฐ๊ณผ ์—†์Œ
    
    --โ—‹ UPPER(), LOWER(), INITCAP()
    SELECT 'oRaCLe' "COL1"
        , UPPER('oRaCLe') "COL2"
        , LOWER('oRaCLe') "COL3"
        , INITCAP('oRaCLe') "COL3"
    FROM DUAL;
    --==>>oRaCLe	ORACLE	oracle	Oracle
    --UPPER() ๋Š” ๋ชจ๋‘ ๋Œ€๋ฌธ์ž๋กœ ๋ณ€ํ™˜
    --LOWER() ๋Š” ๋ชจ๋‘ ์†Œ๋ฌธ์ž๋กœ ๋ณ€ํ™˜
    --INITCAP() ์€ ์ฒซ ๊ธ€์ž๋งŒ ๋Œ€๋ฌธ์ž๋กœ ํ•˜๊ณ  ๋‚˜๋จธ์ง€๋Š” ๋ชจ๋‘ ์†Œ๋ฌธ์ž๋กœ ๋ณ€ํ™˜ํ•˜์—ฌ ๋ฐ˜ํ™˜
    
    --โ€ป ์‹ค์Šต์„ ์œ„ํ•œ ์ถ”๊ฐ€ ๋ฐ์ดํ„ฐ ์ž…๋ ฅ
    INSERT INTO TBL_EMP(EMPNO, ENAME, JOB, MGR, HIREDATE, DEPTNO, COMM)
    VALUES(8002, '์ž„ํ•˜์„ฑ', 'salesman', 7369, SYSDATE,20,100);
    --==>> 1 ํ–‰ ์ด(๊ฐ€) ์‚ฝ์ž…๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    --โ—‹ ํ™•์ธ
    SELECT *
    FROM TBL_EMP;
    --==>>
    /*
    7369	SMITH	CLERK	7902	1980-12-17	800		20
    7499	ALLEN	SALESMAN	7698	1981-02-20	1600	300	30
    7521	WARD	SALESMAN	7698	1981-02-22	1250	500	30
    7566	JONES	MANAGER	7839	1981-04-02	2975		20
    7654	MARTIN	SALESMAN	7698	1981-09-28	1250	1400	30
    7698	BLAKE	MANAGER	7839	1981-05-01	2850		30
    7782	CLARK	MANAGER	7839	1981-06-09	2450		10
    7788	SCOTT	ANALYST	7566	1987-07-13	3000		20
    7839	KING	PRESIDENT		1981-11-17	5000		10
    7844	TURNER	SALESMAN	7698	1981-09-08	1500	0	30
    7876	ADAMS	CLERK	7788	1987-07-13	1100		20
    7900	JAMES	CLERK	7698	1981-12-03	950		30
    7902	FORD	ANALYST	7566	1981-12-03	3000		20
    7934	MILLER	CLERK	7782	1982-01-23	1300		10
    8000	๊น€๋‘˜๋ฆฌ	SALESMAN	7369	2023-10-19			10 -> ํ˜„์šฐ๊ธฐ
    8001	๋ฐ•๋˜์น˜	SALSESMAN	7369	2023-10-19		10	10 -> ๋‹ค์„œ๋‹ˆ
    8002	์ž„ํ•˜์„ฑ	salesman	7369	2023-10-19		100	20
    */
         
    /* 6-๋ฌธ์ œ & ๋‚ด๊ฐ€ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์„ ๋Œ€์ƒ์œผ๋กœ ์˜์—…์‚ฌ์›(์„ธ์ผ์ฆˆ๋งจ)์˜
    --    ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ์ง์ข…๋ช…์„ ์กฐํšŒํ•œ๋‹ค.
    --    ๋˜ํ•œ, ๊ฒ€์ƒ‰๊ฐ’์ด 'sALeSmAN' ์ธ ์กฐ๊ฑด์œผ๋กœ ๊ฒ€์ƒ‰์„ ์ˆ˜ํ–‰ํ•˜๋”๋ผ๋„
    --    ํ•ด๋‹น ์‚ฌ์›๋“ค์„ ์กฐํšŒํ•  ์ˆ˜ ์žˆ๋„๋ก ์ฟผ๋ฆฌ๋ฌธ์„ ๊ตฌ์„ฑํ•œ๋‹ค.
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…"
    FROM TBL_EMP
    WHERE JOB = UPPER('sALeSmAN') OR JOB = LOWER('sALeSmAN');
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…"
    FROM TBL_EMP
    WHERE UPPER(JOB) = 'SALESMAN';
    
    SELECT EMPNO "์‚ฌ์›๋ฒˆํ˜ธ", ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…"
    FROM TBL_EMP
    WHERE UPPER(JOB) = UPPER('sALeSmAN');
    --==>>
    /*
    7499	ALLEN	SALESMAN
    7521	WARD	SALESMAN
    7654	MARTIN	SALESMAN
    7844	TURNER	SALESMAN
    8000	ํ˜„์šฐ๊ธฐ	SALESMAN
    8001	๋‹ค์„œ๋‹ˆ	SALESMAN
    8002	์ž„ํ•˜์„ฑ	salesman
    */
    
    /* 6-๊ฐ™์ด ํ‘ผ ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    SELECT EMPNO, ENAME, JOB
    FROM TBL_EMP
    WHERE ์ง์ข…์ด 'sALeSmAN';
    
    SELECT EMPNO, ENAME, JOB
    FROM TBL_EMP
    WHERE JOB = UPPER('sALeSmAN');
    ==>>
    /*
    7499	ALLEN	SALESMAN
    7521	WARD	SALESMAN
    7654	MARTIN	SALESMAN
    7844	TURNER	SALESMAN
    8000	ํ˜„์šฐ๊ธฐ	SALESMAN
    8001	๋‹ค์„œ๋‹ˆ	SALESMAN
    */
    
    SELECT EMPNO, ENAME, JOB
    FROM TBL_EMP
    WHERE JOB = LOWER('sALeSmAN');
    --==>>
    /*
    8002	์ž„ํ•˜์„ฑ	salesman
    */
    
    SELECT EMPNO, ENAME, JOB
    FROM TBL_EMP
    WHERE JOB = LOWER('sALeSmAN') OR JOB = UPPER('sALeSmAN');
    /*
    7499	ALLEN	SALESMAN
    7521	WARD	SALESMAN
    7654	MARTIN	SALESMAN
    7844	TURNER	SALESMAN
    8000	ํ˜„์šฐ๊ธฐ	SALESMAN
    8001	๋‹ค์„œ๋‹ˆ	SALESMAN
    8002	์ž„ํ•˜์„ฑ	salesman
    */
    
    SELECT EMPNO, ENAME, JOB
    FROM TBL_EMP
    WHERE UPPER(JOB) = UPPER('sALeSmAN');
    --WHERE LOWER(JOB) = LOWER('sALeSmAN');     -- ๊ฐ€๋Šฅ
    --WHERE INITCAP(JOB) = INITCAP('sALeSmAN'); -- ๊ฐ€๋Šฅ
    /*
    7499	ALLEN	SALESMAN
    7521	WARD	SALESMAN
    7654	MARTIN	SALESMAN
    7844	TURNER	SALESMAN
    8000	ํ˜„์šฐ๊ธฐ	SALESMAN
    8001	๋‹ค์„œ๋‹ˆ	SALESMAN
    8002	์ž„ํ•˜์„ฑ	salesman
    */
    
    /* 7-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ์ž…์‚ฌ์ผ์ด 1981๋…„ 9์›” 28์ผ ์ž…์‚ฌํ•œ ์ง์›์˜
    --    ์‚ฌ์›๋ช…, ์ง์ข…๋ช…, ์ž…์‚ฌ์ผ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", HIREDATE "์ž…์‚ฌ์ผ"
    FROM TBL_EMP
    WHERE HIREDATE = '1981-09-28';  -- ๋ฌธ์žํƒ€์ž…์„ ๋‚ ์งœํƒ€์ž…์œผ๋กœ ์ž๋™ ํ˜•๋ณ€ํ™˜
    --                ----          -> ์ˆซ์žํƒ€์ž…
    --                ----------    -> ๋ฌธ์žํƒ€์ž…
    --    -------                   -> ๋‚ ์งœํƒ€์ž…
    --==>> MARTIN	SALESMAN	2023-10-19
    --** ์˜ค๋ผํด์˜ ์ž๋™ํ˜•๋ณ€ํ™˜์„ ๋ฏฟ์ง€์•Š์•„์•ผ ํ•œ๋‹ค.
    
    DESC TBL_EMP;
    
    --โ—‹ TO_DATE()
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", HIREDATE "์ž…์‚ฌ์ผ"
    FROM TBL_EMP
    WHERE HIREDATE = TO_DATE('1981-09-28','YYYY-MM-DD');
    --                        ----------                -> ์ˆซ์žํƒ€์ž…
    --                       ------------               -> ๋ฌธ์žํƒ€์ž…
    --               ---------------------------------- -> ๋‚ ์งœํƒ€์ž…
    --==>> MARTIN	SALESMAN	2023-10-19
    
    /* 8-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ์ž…์‚ฌ์ผ์ด 1921๋…„ 9์›” 28์ผ ์ดํ›„(ํ•ด๋‹น์ผ ํฌํ•จ)
    --    ์ž…์‚ฌํ•œ ์ง์›์˜ ์‚ฌ์›๋ช…, ์ง์ข…๋ช…, ์ž…์‚ฌ์ผ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", HIREDATE "์ž…์‚ฌ์ผ"
    FROM TBL_EMP
    WHERE HIREDATE >= TO_DATE('1981-09-28','YYYY-MM-DD');
    
    --โ€ป ์˜ค๋ผํด์—์„œ๋Š” ๋‚ ์งœ ๋ฐ์ดํ„ฐ์˜ ํฌ๊ธฐ ๋น„๊ต๊ฐ€ ๊ฐ€๋Šฅํ•˜๋‹ค.
    --  ์˜ค๋ผํด์—์„œ๋Š” ๋‚ ์ž ๋ฐ์ดํ„ฐ์— ๋Œ€ํ•œ ํฌ๊ธฐ ๋น„๊ต ์‹œ
    --  ๊ณผ๊ฑฐ๋ณด๋‹ค ๋ฏธ๋ž˜๋ฅผ ๋” ํฐ ๊ฐ’์œผ๋กœ ๊ฐ„์ฃผํ•œ๋‹ค.
    
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ์ž…์‚ฌ์ผ์ด 1981๋…„ 4์›” 2์ผ ๋ถ€ํ„ฐ
    --    1981๋…„ 9์›” 28์ผ ์‚ฌ์ด์— ์ž…์‚ฌํ•œ ์ง์›๋“ค์˜
    --    ์‚ฌ์›๋ช…, ์ง์ข…๋ช…, ์ž…์‚ฌ์ผ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค. (ํ•ด๋‹น์ผ ํฌํ•จ)
    
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", HIREDATE "์ž…์‚ฌ์ผ"
    FROM TBL_EMP
    WHERE HIREDATE >= TO_DATE('1981-04-02','YYYY-MM-DD')
      AND HIREDATE <= TO_DATE('1981-09-28','YYYY-MM-DD');
    --==>>
    /*
    JONES	MANAGER	    1981-04-02
    MARTIN	SALESMAN	1981-09-28
    BLAKE	MANAGER	    1981-05-01
    CLARK	MANAGER	    1981-06-09
    TURNER	SALESMAN	1981-09-08
    */
    
    --โ—‹ BETWEEN โ“ AND โ“‘
    SELECT ENAME "์‚ฌ์›๋ช…", JOB "์ง์ข…๋ช…", HIREDATE "์ž…์‚ฌ์ผ"
    FROM TBL_EMP
    WHERE HIREDATE BETWEEN TO_DATE('1981-04-02','YYYY-MM-DD')
                       AND TO_DATE('1981-09-28','YYYY-MM-DD');
    --==>>
    /*
    JONES	MANAGER	1981-04-02
    MARTIN	SALESMAN	1981-09-28
    BLAKE	MANAGER	1981-05-01
    CLARK	MANAGER	1981-06-09
    TURNER	SALESMAN	1981-09-08
    */
    -----------โ—------------------โ—-------------
    --        1981.4.2            1921.9.28
    
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ๊ธ‰์—ฌ(SAL)๊ฐ€ 2450 ์—์„œ 3000 ๊นŒ์ง€์˜ ์ง์›๋“ค์„ ๋ชจ๋‘ ์กฐํšŒํ•œ๋‹ค.
    SELECT *
    FROM TBL_EMP
    WHERE SAL BETWEEN 2450 AND 3000;
    --==>>
    /*
    7566	JONES	MANAGER	7839	1981-04-02	2975		20
    7698	BLAKE	MANAGER	7839	1981-05-01	2850		30
    7782	CLARK	MANAGER	7839	1981-06-09	2450		10
    7788	SCOTT	ANALYST	7566	1987-07-13	3000		20
    7902	FORD	ANALYST	7566	1981-12-03	3000		20
    */
    -----------โ—------------------โ—-------------
    --        2450                3000
    
    --โ—‹ TBL_EMP ํ…Œ์ด๋ธ”์—์„œ ์ง์›๋“ค์˜ ์ด๋ฆ„์ด
    --    'C'๋กœ ์‹œ์ž‘ํ•˜๋Š” ์ด๋ฆ„๋ถ€ํ„ฐ 'S'๋กœ ์‹œ์ž‘ํ•˜๋Š” ์ด๋ฆ„์ธ ๊ฒฝ์šฐ
    --     ๋ชจ๋“  ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT *
    FROM TBL_EMP
    WHERE ENAME BETWEEN 'C' AND 'S';
    -----------โ—------------------โ—‹-------------    --** ์‚ฌ์ „์‹ ๋ฐฐ์—ด ๊ธฐ์ค€('S'๋กœ๋งŒ ์ด๋ฆ„์ด ์žˆ๋‹ค๋ฉด ๊ฒ€์ƒ‰๋จ)
    --        'C'                 'S'
    /*
    7566	JONES	MANAGER	7839	1981-04-02	2975		20
    7654	MARTIN	SALESMAN	7698	1981-09-28	1250	1400	30
    7782	CLARK	MANAGER	7839	1981-06-09	2450		10
    7839	KING	PRESIDENT		1981-11-17	5000		10
    7900	JAMES	CLERK	7698	1981-12-03	950		30
    7902	FORD	ANALYST	7566	1981-12-03	3000		20
    7934	MILLER	CLERK	7782	1982-01-23	1300		10
    */
    
    SELECT *
    FROM TBL_EMP
    WHERE ENAME BETWEEN 'C' AND 's';
    /*
    7369	SMITH	CLERK	7902	1980-12-17	800		20
    7521	WARD	SALESMAN	7698	1981-02-22	1250	500	30
    7566	JONES	MANAGER	7839	1981-04-02	2975		20
    7654	MARTIN	SALESMAN	7698	1981-09-28	1250	1400	30
    7782	CLARK	MANAGER	7839	1981-06-09	2450		10
    7788	SCOTT	ANALYST	7566	1987-07-13	3000		20
    7839	KING	PRESIDENT		1981-11-17	5000		10
    7844	TURNER	SALESMAN	7698	1981-09-08	1500	0	30
    7900	JAMES	CLERK	7698	1981-12-03	950		30
    7902	FORD	ANALYST	7566	1981-12-03	3000		20
    7934	MILLER	CLERK	7782	1982-01-23	1300		10
    */
    
    --โ€ป <BTWEEN โ“ AND โ“‘>๋Š” ๋‚ ์งœํ˜•, ์ˆซ์žํ˜•, ๋ฌธ์žํ˜• ๋ฐ์ดํ„ฐ์— ๋ชจ๋‘ ์ ์šฉ๋œ๋‹ค.
    --    ๋‹จ, ๋ฌธ์žํ˜•์ด ๊ฒฝ์šฐ ์•„์Šคํ‚ค์ฝ”๋“œ ์ˆœ์„œ๋ฅผ ๋‹ค๋ฅด๊ธฐ ๋•Œ๋ฌธ์—(์‚ฌ์ „์‹ ๋ฐฐ์—ด)
    --    ๋Œ€๋ฌธ์ž๊ฐ€ ์•ž์ชฝ์— ์œ„์น˜ํ•˜๊ณ , ์†Œ๋ฌธ์ž๊ฐ€ ๋’ค ์ชฝ์— ์œ„์น˜ํ•œ๋‹ค.
    --    ๋˜ํ•œ, <BTWEEN โ“ AND โ“‘>๋Š” ํ•ด๋‹น ๊ตฌ๋ฌธ์ด ์ˆ˜ํ–‰๋˜๋Š” ์‹œ์ ์—์„œ
    --    ์˜ค๋ฅผ ๋‚ด๋ถ€์ ์œผ๋กœ๋Š” ๋ถ€๋“ฑํ˜ธ ์—ฐ์‚ฐ์ž์˜ ํ˜•ํƒœ๋กœ ๋ฐ”๋€Œ์–ด ์—ฐ์‚ฐ ์ฒ˜๋ฆฌํ•œ๋‹ค.
    
    --โ€ป ASCOO()
    --๋งค๊ฐœ๋ณ€์ˆ˜๋กœ ๋„ˆ๊ฒจ๋ฐ›์€ ํ•ด๋‹น ๋ฌธ์ž์˜ ์•„์Šคํ‚ค ์ฝ”๋“œ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•œ๋‹ค.
    SELECT ASCII('A') "COL1"
          ,ASCII('B') "COL2"
          ,ASCII('a') "COL3"
          ,ASCII('b') "COL4"
    --FROM DUAL;
    --==>>65	66	97	98
    
    SELECT ENAME, JOB, SAL
    FROM TBL_EMP
    WHERE JOB = 'SALESMAN'
       OR JOB = 'CLOERK';
    
    SELECT ENAME, JOB, SAL
    FROM TBL_EMP
    WHERE JOB IN ('SALESMAN', 'CLOERK');
    
    SELECT ENAME, JOB, SAL
    FROM TBL_EMP
    WHERE JOB =ANY ('SALESMAN', 'CLOERK');
    
    --โ€ป ์œ„์˜ 3๊ฐ€์ง€ ์œ ํ˜•์˜ ์ฟผ๋ฆฌ๋ฌธ์€ ๋ชจ๋‘ ๊ฐ™์€ ๊ฒฐ๊ณผ๋ฅผ ๋ฐ˜ํ™˜ํ•œ๋‹ค.
    --    ํ•˜์ง€๋งŒ, ๋งจ ์œ„์˜ ์ฟผ๋ฆฌ๋ฌธ(OR)์ด ๊ฐ€์žฅ ๋น ๋ฅด๊ฒŒ ์ฒ˜๋ฆฌ๋˜๋‚˜.(์ •๋ง ์–ผ๋งˆ ์•ˆ๋˜์ง€๋งŒ...)
    --    ๋ฌผ๋ก  ๋ฉ”๋ชจ๋ฆฌ์— ๋Œ€ํ•œ ๋‚ด์šฉ์ด ์•„๋‹ˆ๋ผ CPU์— ๋Œ€ํ•œ ๋‚ด์šฉ์ด๋ฏ€๋กœ
    --    ์ด ๋ถ€๋ถ„๊นŒ์ง€ ๊ฐ์•ˆํ•˜์—ฌ ์ฟผ๋ฆฌ๋ฌธ์„ ๊ตฌ์„ฑํ•˜๊ฒŒ ๋˜๋Š” ๊ฒฝ์šฐ๊ฐ€ ๋งŽ์ง€ ์•Š๋‹ค.
    --    -> <IN> <=ANY>๋Š” ์œ„ ์ƒํ™ฉ์—์„œ ๋ชจ๋‘ ๊ฐ™์€ ์—ฐ์‚ฐ ํšจ๊ณผ๋ฅผ ๊ฐ€์ ธ๊ฐ„๋‹ค.
    --        ์ด๋ฅผ ๋ชจ๋‘๋Š” ๋‚ด๋ถ€์ ์œผ๋กœ <OR> ๊ตฌ์กฐ๋กœ ๋ณ€๊ฒฝ๋˜์–ด ์—ฐ์‚ฐ ์ฒ˜๋ฆฌ ๋œ๋‹ค.
    
    -------------------------------------------------------------------------------
    --โ—‹ ์ถ”๊ฐ€ ์‹ค์Šต ํ…Œ์ด๋ธ” ๊ตฌ์„ฑ(TBL_SAWON)
    CREATE TABLE TBL_SAWON
    ( SANO      NUMBER(4)
    , SANAME    VARCHAR2(30)
    , JUBUN     CHAR(13)
    , HIREDATE  DATE        DEFAULT SYSDATE
    , SAL     NUMBER(10)
    );
    --==>> Table TBL_SAWON์ด(๊ฐ€) ์ƒ์„ฑ๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    
    
    SELECT *
    FROM TBL_SAWON;
    --==>> ์กฐํšŒ๊ฒฐ๊ณผ ์—†์Œ
    
    DESC TBL_SAWON;
    --==>>
    /*
    ์ด๋ฆ„       ๋„? ์œ ํ˜•           
    -------- -- ------------ 
    SANO        NUMBER(4)    
    SNAME       VARCHAR2(30) 
    JUBUN       CHAR(13)     
    HIREDATE    DATE         
    SAL         NUMBER(10) 
    */
    
    --โ—‹ ์ƒ์„ฑ๋œ ํ…Œ์ด๋ธ”์— ๋ฐ์ดํ„ฐ ์ž…๋ ฅ(TBL_SAWON)
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1001, '๊ฐ•ํ˜œ์„ฑ', '9710171234567', TO_DATE('2005-01-03', 'YYYY-MM-DD'), 3000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1002, '๋ฐ•๊ฐ€์˜', '9511182234567', TO_DATE('1999-11-23', 'YYYY-MM-DD'), 4000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1003, '๋ฐ•๋‚˜์˜', '9902082234567', TO_DATE('2006-08-10', 'YYYY-MM-DD'), 4000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1004, '์ตœํ˜œ์ธ', '9708112234567', TO_DATE('2015-10-19', 'YYYY-MM-DD'), 5000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1005, '์•„์ด์œ ', '0502034234567', TO_DATE('2010-05-06', 'YYYY-MM-DD'), 1000); 
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1006, '์ดํ•˜์ด', '0609304234567', TO_DATE('2012-06-17', 'YYYY-MM-DD'), 1000); 
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1007, '์ธ์ˆœ์ด', '6510102234567', TO_DATE('1999-08-22', 'YYYY-MM-DD'), 2000); 
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1008, '์„ ๋™์—ด', '6909101234567', TO_DATE('1998-01-10', 'YYYY-MM-DD'), 2000); 
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1009, '์ด์ด๊ฒฝ', '0505053234567', TO_DATE('2011-05-06', 'YYYY-MM-DD'), 1500); 
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1010, '์„ ์šฐ์šฉ๋…€', '6611112234567', TO_DATE('2000-01-16', 'YYYY-MM-DD'), 1300);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1011, '์ด์œค์ˆ˜', '9501061234567', TO_DATE('2009-09-19', 'YYYY-MM-DD'), 4000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1012, '์„ ์šฐ์„ ', '0606064234567', TO_DATE('2011-11-11', 'YYYY-MM-DD'), 2000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1013, '๋‚จ์ง„', '6511111234567', TO_DATE('1999-11-11', 'YYYY-MM-DD'), 2000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1014, '์ด์ฃผํ˜•', '9904171234567', TO_DATE('2009-11-11', 'YYYY-MM-DD'), 2000);
    
    INSERT INTO TBL_SAWON(SANO, SANAME, JUBUN, HIREDATE, SAL)
    VALUES(1015, '๋‚จ๊ถ๋ฏผ', '0202023234567', TO_DATE('2010-10-10', 'YYYY-MM-DD'), 2300);
    
    --โ—‹ ํ™•์ธ
    SELECT *
    FROM TBL_SAWON;
    /*
    1001	๊ฐ•ํ˜œ์„ฑ	9710171234567	2005-01-03	3000
    1002	๋ฐ•๊ฐ€์˜	9511182234567	1999-11-23	4000
    1003	๋ฐ•๋‚˜์˜	9902082234567	2006-08-10	4000
    1004	์ตœํ˜œ์ธ	9708112234567	2010-05-06	5000
    1005	์•„์ด์œ 	0502034234567	2015-10-19	1000
    1006	์ดํ•˜์ด	0609304234567	2012-06-17	1000
    1007	์ธ์ˆœ์ด	6510102234567	1999-08-22	2000
    1008	์„ ๋™์—ด	6909101234567	1998-01-10	2000
    1009	์ด์ด๊ฒฝ	0505053234567	2011-05-06	1500
    1010	์„ ์šฐ์šฉ๋…€	6611112234567	2000-01-16	1300
    1011	์ด์œค์ˆ˜	9501061234567	2009-09-19	4000
    1012	์„ ์šฐ์„ 	0606064234567	2011-11-11	2000
    1013	๋‚จ์ง„	6511111234567	1999-11-11	2000
    1014	์ด์ฃผํ˜•	9904171234567	2009-11-11	2000
    1015	๋‚จ๊ถ๋ฏผ	0202023234567	2010-10-10	2300
    */
    
    /*
    1. ํ™•์ธ
    SELECT *
    FROM ํ…Œ์ด๋ธ”๋ช…
    WHERE SANO = 1005;
    
    2. ์ˆ˜์ •
    UPDATE ํ…Œ์ด๋ธ”๋ช…
    SET ์ˆ˜์ •ํ•œ ๋‚ด์šฉ
    WHERE SANO = 1005;
    */
    
    --โ—‹ ์ปค๋ฐ‹
    COMMIT;
    -- ์ปค๋ฐ‹ ์™„๋ฃŒ.
    
    /* 9-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ '์ด์ฃผํ˜•' ์‚ฌ์›์˜ ๋ฐ์ดํ„ฐ๋ฅผ ์กฐํšŒํ•œ๋‹ค.
    SELECT *
    FROM TBL_SAWON
    WHERE SANAME = '์ด์ฃผํ˜•';
    --==>> 1014	์ด์ฃผํ˜•	9904171234567	2009-11-11	2000
    
    SELECT *
    FROM TBL_SAWON
    WHERE SANAME LIKE '์ด์ฃผํ˜•';
    --==>> 1014	์ด์ฃผํ˜•	9904171234567	2009-11-11	2000
    --** ๋ฌธ์ž์—ด ์กฐํšŒ์‹œ LIKE ์‚ฌ์šฉ๊ฐ€๋Šฅ
    
    --โ€ป LIKE : ๋™์‚ฌ -> ์ข‹์•„ํ•˜๋‹ค
    --          ๋ถ€์‚ฌ -> ~์™€ ๊ฐ™์ด, ~์ฒ˜๋Ÿผ
    
    --โ€ป WILD CARD(CHARACTER) -> ใ€Ž3%ใ€
    --   ใ€ŽLIKEใ€ ์™€ ํ•จ๊ป˜ ์‚ฌ์šฉ๋˜๋Š” ใ€Ž%ใ€๋Š” ๋ชจ๋“  ๊ธ€์ž๋ฅผ ์˜๋ฏธํ•˜๊ณ 
    --   ใ€ŽLIKEใ€ ์™€ ํ•จ๊ป˜ ์‚ฌ์šฉ๋˜๋Š” ใ€Ž_ใ€๋Š” ์•„๋ฌด ๊ธ€์ž ํ•œ ๊ฐœ๋ฅผ ์˜๋ฏธํ•œ๋‹ค.
    
    
    /* 10-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์„ฑ์”จ๊ฐ€ ใ€Ž๊ฐ•ใ€์”จ์ธ ์‚ฌ๋žŒ๋“ค์˜
    --   ์‚ฌ์›๋ช…, ์ฃผ๋ฏผ๋ฒˆํ˜ธ, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT SANAME "์‚ฌ์›๋ช…", JUBUN "์ฃผ๋ฏผ๋ฒˆํ˜ธ", SAL "๊ธ‰์—ฌ";
    FROM TBL_SAWON
    WHERE ์„ฑ์”จ๊ฐ€ '๊ฐ•';
    
    SELECT SANAME "์‚ฌ์›๋ช…", JUBUN "์ฃผ๋ฏผ๋ฒˆํ˜ธ", SAL "๊ธ‰์—ฌ"
    FROM TBL_SAWON
    WHERE SANAME = '๊ฐ•_';
    --==>> ์กฐํšŒ๊ฒฐ๊ณผ ์—†์Œ
    
    SELECT SANAME "์‚ฌ์›๋ช…", JUBUN "์ฃผ๋ฏผ๋ฒˆํ˜ธ", SAL "๊ธ‰์—ฌ"
    FROM TBL_SAWON
    WHERE SANAME LIKE '๊ฐ•__';
    --==>> ๊ฐ•ํ˜œ์„ฑ	9710171234567	3000
    
    SELECT SANAME "์‚ฌ์›๋ช…", JUBUN "์ฃผ๋ฏผ๋ฒˆํ˜ธ", SAL "๊ธ‰์—ฌ"
    FROM TBL_SAWON
    WHERE SANAME LIKE '๊ฐ•%';
    --==>> ๊ฐ•ํ˜œ์„ฑ	9710171234567	3000
    
    /* 11-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์„ฑ์”จ๊ฐ€ <์ด>์”จ์ธ ์‚ฌ์›์˜
    --    ์‚ฌ์›๋ช…, ์ฃผ๋ฏผ๋ฒˆํ˜ธ, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
       
    SELECT SANAME, JUBUN, SAL
    FROM TBL_SAWON
    WHERE SANAME LIKE '์ด%';
    
    /* 12-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์‚ฌ์›์˜ ์ด๋ฆ„์ด <์˜>์œผ๋กœ ๋๋‚˜๋Š” ์‚ฌ์›์˜
    --   ์‚ฌ์›๋ช…, ์ฃผ๋ฏผ๋ฒˆํ˜ธ, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT SANAME, JUBUN, SAL
    FROM TBL_SAWON
    WHERE SANAME LIKE '%์˜';
    --** ์˜ ์•ž์— ๊ธ€์ž๊ฐ€ ์—†์–ด๋„ ์ฐพ์Œ. %๋Š” ์—†๋Š” ๊ธ€์ž๊นŒ์ง€ ํฌํ•จ.
    --==>>
    /*
    ๋ฐ•๊ฐ€์˜	9511182234567	4000
    ๋ฐ•๋‚˜์˜	9902082234567	4000
    */
    
    /* 13-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์‚ฌ์›์˜ ์ด๋ฆ„์ด '์ด'๋ผ๋Š” ๊ธ€์ž๊ฐ€
    --   ํ•˜๋‚˜๋ผ๋„ ํฌํ•จ๋˜์–ด ์žˆ๋‹ค๋ฉด ๊ทธ ์‚ฌ์›์˜
    --   ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
       
    SELECT SANO, SANAME, SAL
    FROM TBL_SAWON
    WHERE SANAME LIKE '%์ด%';
    --==>>
    /*
    1005	์•„์ด์œ 	1000
    1006	์ดํ•˜์ด	1000
    1007	์ธ์ˆœ์ด	2000
    1009	์ด์ด๊ฒฝ	1500
    1011	์ด์œค์ˆ˜	4000
    1014	์ด์ฃผํ˜•	2000
    */
    
    /* 14-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์‚ฌ์›์˜ ์ด๋ฆ„์ด '์ด'๋ผ๋Š” ๊ธ€์ž๊ฐ€
    --   ๋‘ ๋ฒˆ ๋“ค์–ด์žˆ๋Š” ์‚ฌ์›์˜ ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT SANO, SANAME, SAL
    FROM TBL_SAWON
    WHERE SANAME LIKE '%์ด%์ด%';
    --==>>
    /*
    1006	์ดํ•˜์ด	1000
    1009	์ด์ด๊ฒฝ	1500
    */
    
    /* 15-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์‚ฌ์šฐ๋„ˆ์˜ ์ด๋ฆ„์ด '์ด'๋ผ๋Š” ๊ธ€์ž๊ฐ€
    --   ์—ฐ์†์œผ๋กœ ๋‘ ๋ฒˆ ๋“ค์–ด์žˆ๋Š” ์‚ฌ์›์˜
    --   ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT SANO, SANAME, SAL
    FROM TBL_SAWON
    WHERE SANAME LIKE '%์ด์ด%';   
    --==>> 1009	์ด์ด๊ฒฝ	1500
    
    /* 16-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์‚ฌ์›์˜ ์ด๋ฆ„์˜ ๋‘ ๋ฒˆ์งธ ๊ธ€์ž๊ฐ€ 'ํ˜œ'์ธ ์‚ฌ์›์˜
    --   ์‚ฌ์›๋ฒˆํ˜ธ, ์‚ฌ์›๋ช…, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT SANO, SANAME, SAL
    FROM TBL_SAWON
    --WHERE SANAME LIKE '%ํ˜œ%';  --(x) ํ•œ ๊ธ€์ž๋งŒ ์žˆ๋”๋ผ๋„ ๊ฒ€์ƒ‰๋จ
    --WHERE SANAME LIKE '_ํ˜œ_';  --(โ–ณ) ๊ฐ€๋Šฅ์€ ํ•˜์ง€๋งŒ, 3๊ธ€์ž๊ฐ€ ๋„˜์–ด๊ฐ€๋ฉด ๊ฒ€์ƒ‰๋˜ ์ง€ ์•Š์Œ
    WHERE SANAME LIKE '-ํ˜œ%';
    --==>>
    /*
    1001	๊ฐ•ํ˜œ์„ฑ	3000
    1004	์ตœํ˜œ์ธ	5000
    */
    
    /* 17-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์„ฑ์”จ๊ฐ€ '์„ '์”จ์ธ ์‚ฌ์›์˜
    --   ์‚ฌ์›๋ฒˆํ˜ธ, ์ฃผ๋ฏผ๋ฒˆํ˜ธ, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    --** ์„ฑ ์นผ๋Ÿผ์ด ๋ถ„๋ฆฌ๋˜์–ด ์žˆ์ง€ ์•Š๋‹ค๋ฉด, ์ฐพ์„ ์ˆ˜ ์—†์Œ (EX. ์„ ์šฐ๋ผ๋Š” ์„ฑ์”จ๊ฐ€ ์žˆ์Œ)
    SELECT SANO, JUBUN, SAL
    FROM TBL_SAWON
    WHERE SANAME LIKE '์„ %'; --(x)
    
    --โ€ป ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ์„ค๊ณ„ ๊ณผ์ •ใ…‡์„œ
    --     ์„ฑ๊ณผ ์ด๋ฆ„์„ ๋ถ„๋ฆฌํ•˜์—ฌ ์ฒ˜๋ฆฌํ•  ์—…๋ฌด ๊ณ„ํš์ด ์žˆ๋‹ค๋ฉด
    --     (์ง€๊ธˆ ๋‹น์žฅ์€ ์•„๋‹ˆ๋”๋ผ๋„...)
    --     ํ…Œ์ด๋ธ”์—์„œ ์„ฑ ์ปฌ๋Ÿผ๊ณผ ์ด๋ฆ„ ์ปฌ๋Ÿผ์€ ๋ถ„๋ฆฌํ•˜์—ฌ ๊ตฌ์„ฑํ•ด์•ผ ํ•œ๋‹ค.
    
    /* 18-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ TBL_SAWON ํ…Œ์ด๋ธ”์—์„œ ์—ฌ์ง์›๋“ค์˜
    --   ์‚ฌ์›๋ช…, ์ฃผ๋ฏผ๋ฒˆํ˜ธ, ๊ธ‰์—ฌ ํ•ญ๋ชฉ์„ ์กฐํšŒํ•œ๋‹ค.
    SELECT SANAME,JUBUN, SAL
    FROM TBL_SAWON
    WHERE JUBUN LIKE '______2%' OR JUBUN LIKE '______4%';
    
    SELECT SANAME,JUBUN, SAL
    FROM TBL_SAWON
    WHERE JUBUN LIKE '______2______' OR JUBUN LIKE '______4______';
    --==>>
    /*
    ๋ฐ•๊ฐ€์˜	9511182234567	4000
    ๋ฐ•๋‚˜์˜	9902082234567	4000
    ์ตœํ˜œ์ธ	9708112234567	5000
    ์•„์ด์œ 	0502034234567	1000
    ์ดํ•˜์ด	0609304234567	1000
    ์ธ์ˆœ์ด	6510102234567	2000
    ์„ ์šฐ์šฉ๋…€	6611112234567	1300
    ์„ ์šฐ์„ 	0606064234567	2000
    */
    
    SELECT *
    FROM TBL_SAWON;
    
    --โ—‹ ์‹ค์Šต ํ…Œ์ด๋ธ” ์ƒ์„ฑ(TBL_WATCH)
    CREATE TABLE TBL_WATCH
    ( WATCH_NAME    VARCHAR2(20)
    , BIGO          VARCHAR2(100)
    );
    --==>> Table TABL_WATCH์ด(๊ฐ€) ์ƒ์„ฑ๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    SELECT *
    FROM TBL_WATCH;
    
    /* 19-๋ฌธ์ œ & ํ•จ๊ป˜ํ‘ผ๋‚ด์šฉ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    --โ—‹ ๋ฐ์ดํ„ฐ ์ž…๋ ฅ
    INSERT INTO TBL_WATCH(WATCH_NAME, BIGO)
    VALUES('๊ธˆ์‹œ๊ณ„', '์ˆœ๊ธˆ 99.99% ํ•จ์œ ๋œ ์ตœ๊ณ ๊ธ‰ ์‹œ๊ณ„');
    
    INSERT INTO TBL_WATCH(WATCH_NAME, BIGO)
    VALUES('์€์‹œ๊ณ„', '๊ณ ๊ฐ๋งŒ์กฑ๋„ 99.99%์„ ํš๋“ํ•œ ์ตœ๊ณ ์˜ ์‹œ๊ณ„');
    
    --โ—‹ ์ปค๋ฐ‹
    COMMIT;
    --==>> ์ปค๋ฐ‹ ์™„๋ฃŒ.
    
    --โ—‹ TBL_WATCH ํ…Œ์ด๋ธ”์˜ BIGO(๋น„๊ณ ) ์ปฌ๋Ÿผ์—
    --   <99.99%> ๋ผ๋Š” ๊ธ€์ž๊ฐ€ ํฌํ•จ๋œ(๋“ค์–ด์žˆ๋Š”) ํ–‰(๋ ˆ์ฝ”๋“œ)์˜
    --   ๋ฐ์ดํ„ฐ๋ฅผ ์กฐํšŒํ•œ๋‹ค.
    SELECT *
    FROM TBL_WATCH
    WHERE BIGO LIKE '%99.99%';
    --==>>
    /*
    ๊ธˆ์‹œ๊ณ„	์ˆœ๊ธˆ 99.99% ํ•จ์œ ๋œ ์ตœ๊ณ ๊ธ‰ ์‹œ๊ณ„
    ์€์‹œ๊ณ„	๊ณ ๊ฐ๋งŒ์กฑ๋„ 99.99์ ์„ ํš๋“ํ•œ ์ตœ๊ณ ์˜ ์‹œ๊ณ„
    */
    
    SELECT *
    FROM TBL_WATCH
    WHERE BIGO LIKE '%99.99%';
    
    -- ESCAPE 
    --** ์“ฐ๋ ค๊ณ  ํ•˜๋Š” % ์•ž์— ์•ˆ์“ฐ๋Š” ๋ฌธ์ž๋ฅผ ๋„ฃ๊ณ , ESCAPE ๋’ค์— '์•ˆ์“ฐ๋Š”๋ฌธ์ž' ๋กœ ์ž‘์„ฑ
    --** ์•ˆ์“ฐ๋Š” ๋ฌธ์ž: $, \, / ๋“ฑ ๋ฌธ๋ฒ•์ ์œผ๋กœ ์ค‘๋ณต๋˜์ง€ ์•Š๋Š” ๋ฌธ์ž
    
    SELECT *
    FROM TBL_WATCH
    WHERE BIGO LIKE '%99.99\%%' ESCAPE '\';
    --==>> ๊ธˆ์‹œ๊ณ„	์ˆœ๊ธˆ 99.99% ํ•จ์œ ๋œ ์ตœ๊ณ ๊ธ‰ ์‹œ๊ณ„
    
    --โ€ป ESCAPE ๋กœ ์ •ํ•œ ๋ฌธ์ž์˜ ๋‹ค์Œ ํ•œ ๊ธ€์ž๋ฅผ ์™€์ผ๋“œ ์นด๋“œ์—์„œ ํƒˆ์ถœ์‹œ์ผœ๋ผ..
    --   ์ผ๋ฐ˜์ ์œผ๋กœ ์‚ฌ์šฉ ๋นˆ๋„๊ฐ€ ๋‚ฎ์€  ํŠน์ˆ˜๋ฌธ์ž(ํŠน์ˆ˜๊ธฐํ˜ธ)๋ฅผ ์‚ฌ์šฉํ•œ๋‹ค.
    
    --------------------------------------------------------------------------------
    
    --โ– โ– โ–  COMMIT / ROLLBACK โ– โ– โ– --
    
    SELECT *
    FROM TBL_DEPT;
    --==>>
    /*
    10	ACCOUNTING	NEW YORK
    20	RESEARCH	DALLAS
    30	SALES	CHICAGO
    40	OPERATIONS	BOSTON
    */
    
    --โ—‹ ๋ฐ์ดํ„ฐ ์ž…๋ ฅ
    INSERT INTO TBL_DEPT VALUES(50, '๊ฐœ๋ฐœ๋ถ€', '์„œ์šธ');
    --==>> 1 ํ–‰ ์ด(๊ฐ€) ์‚ฝ์ž…๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    SELECT *
    FROM TBL_DEPT;
    --==>>
    /*
    10	ACCOUNTING	NEW YORK
    20	RESEARCH	DALLAS
    30	SALES	CHICAGO
    40	OPERATIONS	BOSTON
    50	๊ฐœ๋ฐœ๋ถ€	์„œ์šธ
    */
    
    /* 
    ** ํ…Œ์ด๋ธ”์€ ๋ฌผ๋ฆฌ์ -ํ•˜๋“œ๋””์Šคํฌ
                ๋…ผ๋ฆฌ์ -ํ…Œ์ด๋ธ”์ŠคํŽ˜์ด์Šค ์— ๋งŒ๋“ค์–ด์ง
       ํ…Œ์ด๋ธ”์— ๋ฐ์ดํ„ฐ ์ž…๋ ฅ์„ ์‹คํ–‰ํ–ˆ๋‹ค ํ•˜๋”๋ผ๋„, 
                ์‹ค์ œ ํ•˜๋“œ๋””์Šคํฌ์— ๋ฌผ๋ฆฌ์ ์œผ๋กœ ์ €์žฅ๋œ๊ฒŒ ์•„๋‹Œ, ๋ฉ”๋ชจ๋ฆฌ์ƒ์— ์ €์žฅ ๋œ ๊ฒƒ
    */
    
    --50๋ฒˆ ๊ฐœ๋ฐœ๋ถ€ ์„œ์šธ...
    --์ด ๋ฐ์ดํ„ฐ๋Š” TBL_DEPT ํ…Œ์ด๋ธ”์ด ์ €์žฅ๋˜์–ด ์žˆ๋Š”
    --ํ•˜๋“œ๋””์Šคํฌ์ƒ์— ๋ฌผ๋ฆฌ์ ์œผ๋กœ ์ ์šฉ๋˜์–ด ์ €์žฅ๋œ ๊ฒƒ์ด ์•„๋‹ˆ๋‹ค.
    --๋ฉ”๋ชจ๋ฆฌ(RAM) ์ƒ์— ์ž…๋ ฅ๋œ ๊ฒƒ์ด๋‹ค.
    
    --โ—‹ ๋กค๋ฐฑ
    ROLLBACK;   -- ํ…Œ์ด๋ธ”์•ˆ์—์„œ 
    
    SELECT *
    FROM TBL_DEPT;
    /*
    10	ACCOUNTING	NEW YORK
    20	RESEARCH	DALLAS
    30	SALES	CHICAGO
    40	OPERATIONS	BOSTON
    */
    -- 50๋ฒˆ ๊ฐœ๋ฐœ๋ถ€ ์„œ์šธ... ์— ๋Œ€ํ•œ ๋ฐ์ดํ„ฐ๊ฐ€ ์†Œ์‹ค ๋˜์—ˆ์Œ์„ ํ™•์ธ(์กด์žฌํ•˜์ง€ ์•Š์Œ)
    
    --โ—‹ ๋‹ค์‹œ๋ฐ์ดํ„ฐ ์ž…๋ ฅ
    INSERT INTO TBL_DEPT VALUES(50, '๊ฐœ๋ฐœ๋ถ€', '์„œ์šธ');
    --==>> 1 ํ–‰ ์ด(๊ฐ€) ์‚ฝ์ž…๋˜์—ˆ์Šต๋‹ˆ๋‹ค.
    
    SELECT *
    FROM TBL_DEPT;
    
    -- 50๋ฒˆ ๊ฐœ๋ฐœ๋ถ€ ์„œ์šธ...
    -- ์ด ใ„ท์ดํ„ฐ๋Š” TBL_DEPT ํ…Œ์ด๋ธ”์ด ์ €์žฅ๋””์–ด ์ž‡๋Š” ํ•˜๋“œ๋””์Šคํฌ ์ƒ์— ์ €์žฅ๋œ ๊ฒƒ์ด ์•„๋‹ˆ๋ผ
    --๋ฉ”๋ชจ๋ฆฌ(RAM) ์ƒ์— ์ž…๋ ฅ๋œ ๊ฒƒ์ด๋‹ค.
    --์ด๋ฅผ... ์‹ค์ œ ํ•˜๋“œ๋””์Šคํฌ ์ƒ์— ๋ฌผ๋ฆฌ์ ์œผ๋กœ ์ €์žฅ๋œ ์ƒํ™ฉ์„ ํ™•์ •ํ•˜๊ธฐ ์œ„ํ•ด์„œ๋Š” 
    --COMMIT์„ ์ˆ˜ํ–‰ํ•ด์•ผ ํ•œ๋‹ค.
    
    COMMIT;
    --==>> ์ปค๋ฐ‹ ์™„๋ฃŒ
    
    --โ—‹ ์ปค๋ฐ‹ ์ดํ›„ ๋‹ค์‹œ ํ™•์ธ
    SELECT *
    FROM TBL_DEPT;
    --==>>
    /*
    10	ACCOUNTING	NEW YORK
    20	RESEARCH	DALLAS
    30	SALES	CHICAGO
    40	OPERATIONS	BOSTON
    50	๊ฐœ๋ฐœ๋ถ€	์„œ์šธ
    */
    
    ROLLBACK;
    --==>> ๋กค๋ฐฑ ์™„๋ฃŒ.
    
    -- ๋กค๋ฐฑ(ROLLBACK)์„ ์ˆ˜ํ–‰ํ•˜์˜€์Œ์—๋„ ๋ถˆ๊ตฌํ•˜๊ณ 
    -- 50๋ฒˆ ์„œ์šธ์€... ์˜ ํ–‰ ํ˜•ํƒœ๋Š” ์†Œ์‹ค๋˜์ง€ ์•Š์•˜์Œ์œผ ํ™•์ธ
    
    --โ€ป COMMIT ์„ ์‹คํ–‰ํ•œ ์ดํ›„๋กœ DML(INSERT, UPDATE, DELETE) ๊ตฌ๋ฌธ์„ ํ†ตํ•ด
    --   ๋ณ€๊ฒฝ๋œ ๋ฐ์ดํ„ฐ๋ฅผ ํœ˜์†Œํ•  ์ˆ˜ ์žˆ๋Š” ๊ฒƒ ๋ฟ...
    --   DML ๋ช…๋ น์„ ์‚ฌ์šฉํ•œ ํ›„ COMMIT์„ ์ˆ˜ํ–‰ํ•˜๊ณ  ๋‚˜์„œ ROLLBACK์„ ์‹คํ–‰ํ•ด๋ด์•ผ
    --   ์•„๋ฌด์†Œ์šฉ์ด ์—†๋‹ค.
    
    --โ—‹ ๋ฐ์ดํ„ฐ ์ˆ˜์ •(UPDATE -> TBL_DEPT)
    --** COMMIT ์ด๋‚˜ ROLLBACK ๋ณด๋‹ค ํ›จ์”ฌ ์ค‘์š”ํ•œ ์ด์•ผ๊ธฐ
    --** CREATE, ALTER ๋Š” AUTO COMMIT!! ์ฃผ์˜ํ•˜๊ธฐ!!
    UPDATE TBL_DEPT
    SET DNAME = '์—ฐ๊ตฌ๋ถ€', LOC = '๊ฒฝ๊ธฐ'
    FROM DEPTNO = 50;