{"id":4614,"date":"2021-11-04T10:52:42","date_gmt":"2021-11-04T01:52:42","guid":{"rendered":"http:\/\/haisins.epac.to\/wordpress\/?p=4614"},"modified":"2021-11-04T10:56:32","modified_gmt":"2021-11-04T01:56:32","slug":"%ec%8b%a0%ea%b7%9c-%ec%b6%94%ea%b0%80-%eb%90%9c-batch-i-o-%ea%b8%b0%eb%8a%a5-%ec%9c%bc%eb%a1%9c-%ec%9d%b8%ed%95%9c-%ea%b2%b0%ea%b3%bc%ea%b0%92-%ec%98%a4%eb%a5%98-%ec%9e%a5%ec%95%a0","status":"publish","type":"post","link":"http:\/\/haisins.synology.me\/wordpress\/?p=4614","title":{"rendered":"\uc2e0\uaddc \ucd94\uac00 \ub41c Batch I\/O \uae30\ub2a5 \uc73c\ub85c \uc778\ud55c \uacb0\uacfc\uac12 \uc624\ub958 \uc7a5\uc560"},"content":{"rendered":"

 <\/p>\n

Table Random Access\ub294 \uc5c4\uccad\ub09c \ubd80\ud558\ub97c \uc720\ubc1c \ud558\ub294 \uc791\uc5c5\uc774\uba70 \ub300\ubd80\ubd84\uc758 \uc131\ub2a5 \uc800\ud558 SQL\uc740 Table Random Access\uc5d0\uc11c \uc2dc\uc791\ub429\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

\"image\"<\/a><\/p>\n

 <\/p>\n

\"image\"<\/a><\/p>\n

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\uc778\ub371\uc2a4 \uc2a4\uce94 \ud6c4 \uc2e4\uc81c \ub370\uc774\ud130\ub97c \uac00\uc838\uc624\uae30 \uc704\ud574 Table Random Access\ub97c \uc218\ud589 \ud569\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

\ud574\ub2f9 \uc791\uc5c5\uc740 DBMS \uc131\ub2a5 \ubd80\ud558\uc758 \uc8fc \uc694\uc778\uc774 \ub418\uba70\u00a0 SQL\ud29c\ub2dd\uc740 \uace7 Random I\/O (\uc77c\ub7c9) \ub97c \uc904\uc774\ub294 \uc77c \uc785\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

Table Random Access \uad00\ub828 \uc131\ub2a5 \ubb38\uc81c\ub97c \uac1c\uc120 \ud558\uae30 \uc704\ud574\u00a0 \uc2e0\uaddc \uc624\ub77c\ud074 \ubc84\uc804 ( 12c \uc774\uc0c1 ) \uc5d0\uc11c\u00a0 Batch I\/O \uae30\ub2a5\uc774 \ucd9c\uc2dc\ub418\uc5c8\uc2b5\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

\"image\"<\/a><\/p>\n

\"image\"<\/a><\/p>\n

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\uc778\ub371\uc2a4 \uc2a4\uce94 \ud6c4 \ucd94\uac00 \uc815\ubcf4\ub97c \uac00\uc838\uc624\uae30 \uc704\ud574 Table Random Access\ub97c \uc218\ud589\ud569\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

\ube48\ubc88\ud55c Table Random Access\ub294 \ud070 \ubd80\ud558\uac00 \ubc1c\uc0dd \ud558\uae30 \ub54c\ubb38\uc5d0 \uc774 \uc791\uc5c5\uc744 \ubaa8\uc544\uc11c\u00a0 \uc77d\uc744 \ube14\ub85d\uc774 \uc77c\uc815\ub7c9 \uc313\uc774\uba74 \ud55c\uaebc\ubc88\uc5d0 I\/O \ucc98\ub9ac\ud558\uac8c \ub429\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

\uc7a5\uc560 \ud604\uc0c1 \ubc1c\uc0dd<\/u><\/span><\/strong><\/p>\n

\u00a0<\/span><\/u><\/strong><\/p>\n

\uae30\uc874\uc758 \uc778\ub371\uc2a4 \uc2a4\uce94\ub9cc\uc73c\ub85c \uacb0\uacfc \uc9d1\ud569\uc758 \uc815\ub82c(\uc778\ub371\uc2a4 \uceec\ub7fc \uae30\uc900)\uc774 \ubcf4\uc7a5\ub418\uc5c8\uc2b5\ub2c8\ub2e4. \ud558\uc9c0\ub9cc Batch I\/O \uc791\ub3d9 \uc2dc \uc774\ub7ec\ud55c \ubc29\uc2dd\uc758 \uacb0\uacfc \uc9d1\ud569 \uc815\ub82c\uc740 \ubcf4\uc7a5\ub418\uc9c0 \uc54a\uc2b5\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

#. \uc815\ub82c \uad00\ub828 \uc8fc\uc758 \uc0ac\ud56d<\/p>\n

*. \uc778\ub371\uc2a4\ub294 \uc815\ub82c\ub41c \uc0c1\ud0dc\ub85c \uc800\uc7a5\ub418\uc5b4 \uc788\uace0, \uc778\ub371\uc2a4 \uc2a4\uce94\uc744 \ud1b5\ud574 Table Random Access\uc758 \uacb0\uacfc \uc9d1\ud569\uc740 \uacbd\uc720\ud55c \uc778\ub371\uc2a4\uc758 \uc815\ub82c \uc21c\uc11c\uc640 \uc77c\uce58\ud569\ub2c8\ub2e4. (Batch I\/O \uae30\ub2a5 False \uc2dc)<\/p>\n

*. Batch I\/O \uae30\ub2a5\uc744 \uc791\ub3d9 \uc2dc\ud0a4\uba74 \uc774\ub7ec\ud55c \uc778\ub371\uc2a4\ub97c \ud1b5\ud55c \uacb0\uacfc \uc9d1\ud569\uc758 \uc815\ub82c\ubcf4\uc7a5\uc740 \ub354\uc774\uc0c1 \ubd88\uac00\ub2a5 \ud569\ub2c8\ub2e4. Table Random Access\u00a0 \uc790\uccb4\ub97c Batch \ubc29\uc2dd\uc751\ub85c \ucc98\ub9ac\ud558\uae30 \ub54c\ubb38\uc5d0 \uc21c\ucc28\uc801\uc73c\ub85c \ud14c\uc774\ube14\uc744 Access\ud559\uc9c0 \uc54a\uac8c \ub418\uae30 \ub54c\ubb38\uc785\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

#. \uacb0\uacfc \uc9d1\ud569\uc758 \uc815\ub82c\uc774 \ubcf4\uc7a5\ub418\uc9c0 \uc54a\ub294 CASE ( Batch I\/O \uae30\ub2a5 True \uc2dc)<\/p>\n

\"image\"<\/a><\/p>\n

 <\/p>\n

 <\/p>\n

\uc7a5\uc560 \ubc29\uc9c0 \ubc29\ubc95<\/u><\/span><\/strong><\/p>\n

\u00a0<\/span><\/u><\/p>\n

\uc624\ub77c\ud074 18c \ubc84\uc804 \uc774\uc0c1 \ubd80\ud130\ub294 \uc815\ub82c\uc774 \ud544\uc694\ud55c SQL\uc740 \ubc18\ub4dc\uc2dc ORDER BY \uc808\uc744 \uae30\uc785\ud558\uac70\ub098 Batch I\/O \uae30\ub2a5\uc744 \ub054\uc73c\ub85c\uc368 \uacb0\uacfc\uc9d1\ud569 \uc624\ud508 \uc804\/\ud6c4 \uac19\uc74c\uc744 \ubcf4\uc7a5\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/span><\/strong><\/p>\n

 <\/p>\n

\"image\"<\/a><\/p>\n

 <\/p>\n

*. \uc815\ub82c\uc774 \ud544\uc694\ud55c SQL\uc740 \ubc18\ub4dc\uc2dc ORDER BY \ubb38\uc744 \uc0ac\uc6a9\ud574\uc57c \ud569\ub2c8\ub2e4.<\/p>\n

*. \uae30\uc885\uc758 INDEX, INDEX_ASC, INDEX_DESC \ud78c\ud2b8\ub4f1\uc73c\ub85c \uc815\ub82c\uc744 \ubcf4\uc7a5\ud588\ub358 SQL\uc5d0 ORDER BY\ub97c \ubc18\ub4dc\uc2dc \ucd94\uac00 \ud574\uc57c \ud569\ub2c8\ub2e4.<\/p>\n

 <\/p>\n

 <\/p>\n

Batch I\/O \uae30\ub2a5 \ub044\uae30<\/u><\/span><\/strong><\/p>\n

\"image\"<\/a><\/p>\n

 <\/p>\n

_optimizer_batch_table_access_by_rowid \ub97c FALSE \ub85c \ubcc0\uacbd\ud574\uc11c \ud574\uacb0 \uac00\ub2a5 \ud569\ub2c8\ub2e4.<\/p>\n","protected":false},"excerpt":{"rendered":"

  Table Random Access\ub294 \uc5c4\uccad\ub09c \ubd80\ud558\ub97c \uc720\ubc1c \ud558\ub294 \uc791\uc5c5\uc774\uba70 \ub300\ubd80\ubd84\uc758 \uc131\ub2a5 \uc800\ud558 SQL\uc740 Table Random Access\uc5d0\uc11c \uc2dc\uc791\ub429\ub2c8\ub2e4.       \uc778\ub371\uc2a4 \uc2a4\uce94 \ud6c4 \uc2e4\uc81c \ub370\uc774\ud130\ub97c \uac00\uc838\uc624\uae30 \uc704\ud574 Table Random Access\ub97c \uc218\ud589 \ud569\ub2c8\ub2e4.   \ud574\ub2f9 \uc791\uc5c5\uc740 DBMS \uc131\ub2a5 \ubd80\ud558\uc758 \uc8fc \uc694\uc778\uc774 \ub418\uba70\u00a0 SQL\ud29c\ub2dd\uc740 \uace7 Random I\/O (\uc77c\ub7c9) \ub97c \uc904\uc774\ub294 \uc77c \uc785\ub2c8\ub2e4.   Table Random Access \uad00\ub828 […]<\/p>\n","protected":false},"author":1,"featured_media":4522,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"spay_email":""},"categories":[14],"tags":[1209,1207,1211,1210,1208,1212],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/haisins.synology.me\/wordpress\/wp-content\/uploads\/2021\/11\/troubleshoot.png?fit=680%2C345","amp_enabled":true,"_links":{"self":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4614"}],"collection":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4614"}],"version-history":[{"count":2,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4614\/revisions"}],"predecessor-version":[{"id":4616,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4614\/revisions\/4616"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/media\/4522"}],"wp:attachment":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4614"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4614"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4614"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}