{"id":5387,"date":"2002-03-03T19:28:02","date_gmt":"2002-03-03T10:28:02","guid":{"rendered":"https:\/\/sonlab.mycafe24.com\/wp\/%ea%b4%80%ea%b3%84%ed%98%95-%eb%8d%b0%ec%9d%b4%ed%84%b0%eb%b2%a0%ec%9d%b4%ec%8a%a42-table-keys\/"},"modified":"2002-03-03T19:28:02","modified_gmt":"2002-03-03T10:28:02","slug":"%ea%b4%80%ea%b3%84%ed%98%95-%eb%8d%b0%ec%9d%b4%ed%84%b0%eb%b2%a0%ec%9d%b4%ec%8a%a42-table-keys","status":"publish","type":"post","link":"http:\/\/sonbm.com\/wp\/%ea%b4%80%ea%b3%84%ed%98%95-%eb%8d%b0%ec%9d%b4%ed%84%b0%eb%b2%a0%ec%9d%b4%ec%8a%a42-table-keys\/","title":{"rendered":"\uad00\uacc4\ud615 \ub370\uc774\ud130\ubca0\uc774\uc2a4(2)-Table Keys"},"content":{"rendered":"

\uc774\ubbf8 \uc55e\uc5d0\uc11c PK(Primary Key), FK(Foreign Key)\uc640 \uac19\uc740 \uac83\uc744 \ubd24\uc2b5\ub2c8\ub2e4. \uc9c0\uae08\uae4c\uc9c0 \ucc28\uadfc\ucc28\uadfc \uc0b4\ud3b4\ubcf4\uc168\ub2e4\uba74 \ub300\ucda9 \uc5b4\ub5a0\ud55c \uac83\uc778\uc9c0 \ub290\ub08c\uc740 \uc624\uaca0\uc9c0\ub9cc \uc774\ubc88 \uc2dc\uac04\uc5d0\ub294 \ubcf4\ub2e4 \uad6c\uccb4\uc801\uc73c\ub85c \uc608\ub97c \ub4e4\uc5b4 \uc124\uba85\uc744 \ud558\uaca0\uc2b5\ub2c8\ub2e4.<\/font><\/p>\n

    \n
  1. \ud14c\uc774\ube14\uc758 \ud0a4(Key)<\/b>\n

    \ud14c\uc774\ube14\uc5d0\uc11c \ud0a4(Key)\ub294 \uc5b4\ub5a4 \ud589(Row,\ub808\ucf54\ub4dc)\uc744 \ub2e4\ub978 \ud589\uacfc \uad6c\ubd84\ub418\uac8c \ud558\ub294 \uceec\ub7fc \ub610\ub294 \uceec\ub7fc\ub4e4\uc758 \uc9d1\ud569\uc744 \ub9d0\ud569\ub2c8\ub2e4.
    \n\uc774 \uc911\uc5d0\uc11c \uadf8 \ud589\uc744 \uc720\uc77c\ud558\uac8c \uad6c\ubd84\ud574 \uc8fc\ub294 \ud0a4\ub97c Primary Key\ub77c \ud558\uace0, \uc5ec\ub7ec \ud14c\uc774\ube14\uac04\uc758 \uc0c1\ud638 \uad00\uacc4(Relationship)\uc744 \uc704\ud55c \ud0a4\ub97c Foreign Key\ub77c\uace0 \ud569\ub2c8\ub2e4.
    \n\uc774\ub807\uac8c \ub9d0\ub85c\ub9cc \ud558\uba74 \uc798 \uc774\ud574\uac00 \uc548\ub418\ub2c8\uae4c \uc608\ub97c \ub4e4\uc5b4 \uc124\uba85\ub4dc\ub9ac\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n

  2. Primary Key<\/b>
    \n\ud2b9\uc815 \ud589\uc744 \ub2e4\ub978 \ud589\uacfc \uc720\uc77c\ud558\uac8c \uad6c\ubd84\ud560 \uc218 \uc788\ub294 \uceec\ub7fc \ub610\ub294 \uceec\ub7fc’\ub4e4’\uc744 \ub9d0\ud569\ub2c8\ub2e4.
    \n\uc544\ub798\uc758 \ub450 \ud14c\uc774\ube14\uc744 \ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n


    \n\uc0ac\uc6d0 \ud14c\uc774\ube14\uc5d0\uc11c\ub294 \uc0ac\uc6d0 \ubc88\ud638\uac00 Primary Key\uac00 \ub418\uace0, \ubd80\uc11c \ud14c\uc774\ube14\uc5d0\uc11c\ub294 \ubd80\uc11c \ubc88\ud638\uac00 Primary Key\uac00 \ub429\ub2c8\ub2e4. \uc65c \uadf8\ub7f0\uc9c0\ub294 \uc124\uba85 \uc548\ud574\ub3c4 \uc544\uc2e4 \uac83 \uac19\uace0…
    \n\uc774\ub7ec\ud55c Primary Key\uc758 \ud2b9\uc9d5\uc740,<\/p>\n

      \n
    • \uc808\ub300\ub85c Null \uac12\uc744 \uac00\uc9c8 \uc218 \uc5c6\uc2b5\ub2c8\ub2e4.
      \n\ub2f9\uc5f0\ud558\uaca0\uc8e0. \uc720\uc77c\ud558\uac8c \uad6c\ubd84\ud560 \uc218 \uc788\ub294 \uac12\uc744 \uc785\ub825\ud558\uc9c0 \uc54a\uc73c\uba74 \uc5b4\uca4c\uaca0\ub2e4\ub294 \uac81\ub2c8\uae4c.<\/p>\n
    • \ub2e4\ub978 \ud589\uacfc \uc911\ubcf5\ub41c \uac12\uc744 \uac00\uc9c8 \uc218 \uc5c6\uc2b5\ub2c8\ub2e4.
      \n\uc911\ubcf5\ub41c \uac12\uc744 \uac00\uc9c4\ub2e4\uba74 \uadf8\uac83\uc774 Primary Key\uac00 \uc548\ub418\ub294 \uac74 \ub2f9\uc5f0\ud558\uc8e0. \uc8fc\ubbfc\ub4f1\ub85d\ubc88\ud638\uac00 \uac19\uc740 \uc0ac\ub78c\uc774 \ub458 \uc774\uc0c1\uc774\ub77c\ub294 \uac83\uacfc \uac19\uc73c\ub2c8\uae4c\uc694.<\/p>\n
    • \uac12\uc744 \ubcc0\uacbd\ud560 \uc218 \uc5c6\uc2b5\ub2c8\ub2e4.
      \n\uc778\ud130\ub137 \uc0ac\uc774\ud2b8\uc5d0 \ud68c\uc6d0 \uac00\uc785\uc744 \ud558\uba74 \uc65c ID\ub9cc\uc740 \ubc14\uafc0 \uc218 \uc5c6\uc744\uae4c\uc694. \ubc14\ub85c ID\uac00 Primary Key\ub85c \uc124\uc815\ub418\uc5b4 \uc788\uae30 \ub54c\ubb38\uc774\uc8e0.<\/p>\n
    • Primary Key\uc758 \uc18d\uc131\uc740 NN, ND\uc785\ub2c8\ub2e4.<\/ul>\n

      \uc704\uc5d0\uc11c \uc774\ubbf8 \uc124\uba85\ud588\ub124\uc694.
      \n\uc774\uc0c1 Primary Key\uc758 \ud2b9\uc9d5\uc740 \uc124\uba85\ub41c \uac83 \uac19\uace0<\/p>\n

        \n
      • Primary Key\ub294 PK\ub85c \ud45c\uc2dc\ud558\uace0,\n
      • \ud14c\uc774\ube14\uc5d0\uc11c \uc138\ub85c\ub85c \ub450 \uc904\uc744 \uae0b\ub294\ub2e4\ub294 \uac83<\/ul>\n

        \uae4c\uc9c0 \uc54c\uc544\ub450\uba74 \uc644\ubcbd\ud558\uaca0\ub124\uc694. \uc704\uc758 \uadf8\ub9bc\uc744 \ubcf4\uba74 \ub178\ub780\uc0c9 \uceec\ub7fc\uc758 \uc624\ub978\ucabd\uc774 \ub450\uc904\ub85c \ud45c\uc2dc\ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4. \ubc14\ub85c \uc138\ub85c \ub450\uc904 \ud45c\uc2dc\ub41c \ubd80\ubd84\uae4c\uc9c0\uac00 Primary Key\ub77c\ub294 \uac83\uc744 \ub098\ud0c0\ub0b4\ub294 \uac83\uc774\uc8e0.<\/p>\n

      • Composite Key<\/b>\n

        Composite\ub294 ‘\ud63c\ud569’\uc774\ub77c\ub294 \ub73b\uc785\ub2c8\ub2e4. \ud63c\ud569\ud55c \ud0a4\ub77c\ub294 \uac83\uc774 \ubb34\uc5bc\uae4c\uc694?
        \n\ubc14\ub85c \uba87 \uac1c\uc758 \uceec\ub7fc\uc774 \ubaa8\uc5ec\uc11c \ud558\ub098\uc758 Primary Key\ub97c \uc774\ub8f0 \ub54c \uc774\ub7f0 \ub9d0\uc744 \uc501\ub2c8\ub2e4.
        \nPrimary Key\ub294 \ud558\ub098\ub77c\uace0 \ud588\ub294\ub370 \ubb34\uc2a8 \ub9d0\uc774\ub0d0?\uace0 \ub418\ubb3c\uc73c\uc2e4 \ubd84\ub3c4 \uacc4\uc2dc\uaca0\uc9c0\ub9cc \ub2e4\uc74c \uadf8\ub9bc\uc744 \ubcf4\uc2dc\uc8e0.<\/p>\n


        \n\uc67c\ucabd\uc758 EMPLOYEE \ud14c\uc774\ube14\uc740 \uc774\ubbf8 \uc6b0\ub9ac\uac00 \uc54c\ub4ef\uc774 Primary Key\uac00 \ud558\ub098\uc778 \uc9c0\uadf9\ud788 \ud3c9\ubc94\ud55c \ud14c\uc774\ube14\uc785\ub2c8\ub2e4.
        \n\uadf8\ub7f0\ub370 \uc624\ub978\ucabd\uc758 EMPLOYEE SKILL \ud14c\uc774\ube14\uc740 \uc5b4\ub5bb\uc2b5\ub2c8\uae4c?
        \n\ub450 \uac1c\uc758 \uceec\ub7fc\uc5d0 \ubaa8\ub450 PK\ub77c\uace0 \ud45c\uc2dc\ud558\uace0 \ub450\uac1c\uc758 \uceec\ub7fc \ub2e4\uc74c\uc5d0 \uc138\ub85c \ub450\uc904\uc744 \ud45c\uc2dc\ud558\uc5ec \ub450 \uac1c \ubaa8\ub450 Primary Key\ub77c\uace0 \ub098\ud0c0\ub0b4\uace0 \uc788\uc2b5\ub2c8\ub2e4. \uc5b4\ucc0c\ub41c \uc77c\uc77c\uae4c\uc694?<\/p>\n

        \uc6b0\ub9ac\uac00 \uc5ec\ub7ec \uac1c\uc758 \ud14c\uc774\ube14\uc744 \uad6c\uc131\ud558\ub2e4 \ubcf4\uba74 \uc704\uc640 \uac19\uc774 \ud558\ub098\uc758 \uceec\ub7fc\ub9cc\uc73c\ub85c\ub294 \ud574\ub2f9 \ud589(\ub808\ucf54\ub4dc)\ub97c \uc720\uc77c\ud558\uac8c \uc2dd\ubcc4\ud560 \uc218 \uc5c6\uc744 \uacbd\uc6b0\uac00 \uc0dd\uae41\ub2c8\ub2e4. \uc704\uc758 \uc608\ub97c \ubcf4\uba74, Employee Number\uac00 \uc911\ubcf5\uc774 \ub418\uace0 Skill Number\ub3c4 \uc911\ubcf5\uc774 \ub418\uc9c0\ub9cc \ub450 \uceec\ub7fc\uc744 \ud569\uccd0\uc11c \ud558\ub098\ub85c \ubcf4\uc558\uc744 \ub54c\ub294 \uc720\uc77c\ud55c \uad6c\ubd84\uc744 \ud560 \uc218 \uc788\uac8c \ub429\ub2c8\ub2e4. \uc989 101\uc740 \ub450 \uac1c\uac00 \uc788\uc9c0\ub9cc 101-CS101\uacfc 101-ENG101\ub294 \uc11c\ub85c \uad6c\ubd84 \uac00\ub2a5\ud569\ub2c8\ub2e4. \ub9c8\ucc2c\uac00\uc9c0\ub85c 103\ub3c4 103-ENG101\uacfc 103-PSY101\uacfc \uac19\uc774 \ud588\uc744 \uacbd\uc6b0\uc5d0\ub294 \ube44\ub85d 103\uc774 \uc911\ubcf5\ub418\ub354\ub77c\ub3c4 Skill Number\uc640 \ud63c\ud569\ud558\uc5ec \ud558\ub098\uc758 Key\ub85c \uc778\uc2dd\ud588\uc744 \uacbd\uc6b0\uc5d0\ub294 \ud558\ub098\uc758 Primary Key \uc5ed\ud560\uc744 \ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.
        \n\uc774\uc640 \uac19\uc774 \ub450 \uac1c \uc774\uc0c1\uc758 \uceec\ub7fc \uc870\ud569\uc73c\ub85c \uc774\ub8e8\uc5b4\uc9c4 Primary Key\ub97c Composite Key\ub77c\uace0 \ud569\ub2c8\ub2e4.
        \n\ub530\ub77c\uc11c Composite Key \uc804\uccb4\ub294 \ub2e4\ub978 \ud589\uacfc \uc911\ubcf5\ub418\uc5b4\uc11c\ub294 \uc548\ub418\uc9c0\ub9cc \uadf8 \uc77c\ubd80 \uceec\ub7fc\uc740 \uc911\ubcf5\ub418\uc5b4\ub3c4 \ub429\ub2c8\ub2e4. \uc989 Composite Key \uc804\uccb4\uc758 \uc720\uc77c\uc131(Unique)\ub9cc \uc720\uc9c0\ud558\uba74 \ub41c\ub2e4\ub294 \ub9d0\uc774\uc8e0.<\/p>\n

      • Foreign Key<\/b>\n

        Foreign Key\ub294 \uadf8 \uc774\ub984\uc5d0\uc11c\ub3c4 \ub4dc\ub7ec\ub098\ub4ef\uc774 \uc678\ubd80\uc640\uc758 \uc5f0\uad00\uc744 \uace0\ub824\ud55c \ud0a4\uc785\ub2c8\ub2e4. \uc989 \ub2e4\ub978 \ud14c\uc774\ube14\uacfc \uc5f0\uacb0 \uace0\ub9ac\ub97c \ud558\ub294 \uc5ed\ud560\uc744 \ud569\ub2c8\ub2e4.<\/p>\n

        \uc544\ub798 \uadf8\ub9bc\uc744 \ubcf4\uc8e0.<\/p>\n

        <\/p>\n

        EMPLOYEE \ud14c\uc774\ube14\uacfc EMPLOYEE SKILL \ud14c\uc774\ube14 \uc0ac\uc774\uc5d0 \ub3d9\uc77c\ud55c \uceec\ub7fc\uc774 \uc788\uc2b5\ub2c8\ub2e4. Employee \uceec\ub7fc\uc774 \ub3d9\uc77c\ud558\uc8e0. \uc774\ub54c EMPLOYEE \ud14c\uc774\ube14\uacfc EMPLOYEE SKILL \ud14c\uc774\ube14\uc5d0\uc11c Employee Number\ub294 Primary Key\uc785\ub2c8\ub2e4. \uadf8\ub7ec\uba74\uc11c EMPLOYEE SKILL\uc758 Employee Number\ub294 EMPLOYEE \ud14c\uc774\ube14\uc744 \uc5f0\uacb0\ud574\uc8fc\ub294 \uc5ed\ud560\uc744 \ud569\ub2c8\ub2e4. \uadf8\ub798\uc11c Foreign Key\uac00 \ub418\ub294 \uac83\uc785\ub2c8\ub2e4.<\/p>\n

        EMPLOYEE \ud14c\uc774\ube14\uacfc DEPARTMENT \ud14c\uc774\ube14\uc744 \uc5f0\uacb0\uc2dc\ud0a4\ub294 \uacf5\ud1b5 \uceec\ub7fc\uc740 Department Number\uc785\ub2c8\ub2e4. Deplartment Number\ub294 EMPLOYEE \ud14c\uc774\ube14\uc5d0\uc11c\ub294 DEPARTMENT \ud14c\uc774\ube14\uacfc \uc5f0\uacb0\uc2dc\ucf1c\uc8fc\ub294 Foregin Key \uc5ed\ud560\uc744 \ud558\uc9c0\ub9cc DEPARTMENT \ud14c\uc774\ube14\uc5d0\uc11c\ub294 Primary Key \uc5ed\ud560\uc744 \ud569\ub2c8\ub2e4.<\/p>\n

        \ub9d0\ub85c \ud480\uc790\ub2c8 \ub354 \ud5e4\uae54\ub9b4 \uac83 \uac19\ub124\uc694. \uc704\uc758 \uadf8\ub9bc\uc744 \uc790\uc138\ud788 \ubcf4\uc2dc\uba74 \ucda9\ubd84\ud788 \uc774\ud574\uac00 \ub420 \uac83\uc785\ub2c8\ub2e4. <\/p>\n

        \uc704\uc758 \uadf8\ub9bc\uc5d0\uc11c \ud654\uc0b4\ud45c\uc758 \ubc29\ud5a5\uc73c\ub85c \ubcf4\uc558\uc744 \ub54c, \ud654\uc0b4\ud45c\uac00 \uac00\ub9ac\ud0a4\uace0 \uc788\ub294 \ud14c\uc774\ube14\uc774 Dependent \ud14c\uc774\ube14\uc774 \ub418\uace0 \uadf8 \ubc18\ub300\uac00 Parente \ud14c\uc774\ube14\uc774 \ub429\ub2c8\ub2e4. \uc989 Foreign Key\uac00 \uc788\ub294 \ud14c\uc774\ube14\uc774 Dependent \ud14c\uc774\ube14\uc774 \ub429\ub2c8\ub2e4. <\/ol>\n

        \uc774\uc0c1 \ub3d9\uc8fc\uc544\ube60 \uc190\ubcd1\ubaa9\uc774\uc5c8\uc2b5\ub2c8\ub2e4.
        \n<\/p>\n","protected":false},"excerpt":{"rendered":"

        \uc774\ubbf8 \uc55e\uc5d0\uc11c PK(Primary Key), FK(Foreign Key)\uc640 \uac19\uc740 \uac83\uc744 \ubd24\uc2b5\ub2c8\ub2e4. \uc9c0\uae08\uae4c\uc9c0 \ucc28\uadfc\ucc28\uadfc \uc0b4\ud3b4\ubcf4\uc168\ub2e4\uba74 \ub300\ucda9 \uc5b4\ub5a0\ud55c \uac83\uc778\uc9c0 \ub290\ub08c\uc740 \uc624\uaca0\uc9c0\ub9cc \uc774\ubc88 \uc2dc\uac04\uc5d0\ub294 \ubcf4\ub2e4 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[84],"tags":[85,78,86,87,80,88,28,89],"class_list":["post-5387","post","type-post","status-publish","format-standard","hentry","category-sql","tag-db","tag-it","tag-oracle","tag-sql","tag-80","tag-88","tag-28","tag-89"],"_links":{"self":[{"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/posts\/5387","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/comments?post=5387"}],"version-history":[{"count":0,"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/posts\/5387\/revisions"}],"wp:attachment":[{"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/media?parent=5387"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/categories?post=5387"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/sonbm.com\/wp\/wp-json\/wp\/v2\/tags?post=5387"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}