{"id":612,"date":"2015-11-05T08:47:13","date_gmt":"2015-11-05T08:47:13","guid":{"rendered":"http:\/\/haisins.epac.to\/wordpress\/?p=612"},"modified":"2015-11-05T08:47:13","modified_gmt":"2015-11-05T08:47:13","slug":"%ec%a1%b0%ec%9d%b8%ec%9d%98-%ed%8a%9c%eb%8b%9d-%eb%b0%a9%eb%b2%95-1","status":"publish","type":"post","link":"http:\/\/haisins.synology.me\/wordpress\/?p=612","title":{"rendered":"\uc870\uc778\uc758 \ud29c\ub2dd \ubc29\ubc95 -1"},"content":{"rendered":"

\uc870\uc778\uc740 2\uac1c \uc774\uc0c1\uc758 \ud14c\uc774\ube14\ub4e4\uc744 Relation Key\ub85c \uc5f0\uacb0\ud558\uc5ec Merge\uc2dc\ud0a4\ub294 \uac83\uc744 \ub9d0\ud55c\ub2e4.<\/p>\n

<\/p>\n

\uc870\uc778 \uc885\ub958<\/b><\/p>\n

-\uc870\uc778 \uba54\uc18c\ub4dc : Nested Loop Join, Sort Merge Join, Hash Join-<\/p>\n

-\uc870\uc778 \ud0c0\uc785 : Basic(Natural) Join, Outer Join, Semi Join, Anti Join \ub4f1<\/p>\n

<\/p>\n

Relation<\/b><\/p>\n

-WHERE\uc808\uc5d0 \uc870\uc778 \uc870\uac74\uc774 \ub204\ub77d\ub418\uac70\ub098 \uc11c\ub85c Relation\uc744 \uac16\uc9c0 \uc54a\ub294 \ud14c\uc774\ube14\uac04\uc758 \uc870\uc778\uc73c\ub85c \uc778\ud574 M:M Relation\uc774 \ubc1c\uc0dd\ud560 \uc218 \uc788\uc74c<\/p>\n

<\/p>\n

Cartesian Product<\/b><\/p>\n

-2\uac1c\uc758 \uc9d1\ud569\uc774 Relation Key\ub85c \uc5f0\uacb0\ub418\uc9c0 \ubabb\ud558\ub294 \uacbd\uc6b0\uc758 \uc870\uc778 Relation<\/p>\n

-\uc77c\ubc18\uc801\uc73c\ub85c \uc798\ubabb \uc791\uc131\ub41c SQL\uc5d0\uc11c \ube44\ub86f\ub418\uba70 \uc131\ub2a5\uc5d0 \uc88b\uc9c0 \uc54a\uc73c\ubbc0\ub85c \uaf2d \ud544\uc694\ud55c \uacbd\uc6b0\uc5d0\ub9cc \uc0ac\uc6a9<\/p>\n

<\/p>\n

\uc870\uc778(join)\uc758 \uc608<\/b><\/p>\n

SQL> SELECT c.cust_last_name, c.cust_first_name, <\/p>\n

            co.country_id,  co.country_name<\/p>\n

     FROM   customers c, countries co<\/p>\n

     WHERE  c.country_id = co.country_id <\/span>\uf0e7 \uc870\uc778 \uc220\uc5b4<\/p>\n

     AND    co.country_id = \u2018JP\u2019           <\/span>\uf0e7 \ube44\uc870\uc778 \uc220\uc5b4 (Predicates)<\/p>\n

     OR     c.coust_id = 205 ;             <\/span>\uf0e7 \ub2e8\uc77c\ud589 \uc220\uc5b4 (Predicates)<\/p>\n

<\/p>\n

\uc870\uc778 \uc220\uc5b4 : \uc870\uc778\uc5d0 \uc788\ub294 \ub450 \ud14c\uc774\ube14\uc758 \uc5f4\uc744 \uacb0\ud569\ud558\ub294 WHERE \uc808\uc5d0 \uc788\ub294 \uc220\uc5b4<\/p>\n

\ube44\uc870\uc778 \uc220\uc5b4 : \ud558\ub098\uc758 \ud14c\uc774\ube14\ub9cc \ucc38\uc870\ud558\ub294 WHERE \uc808\uc5d0 \uc788\ub294 \uc220\uc5b4<\/p>\n

\ub2e8\uc77c\ud589 \uc220\uc5b4 : \uace0\uc720 \ub610\ub294 PK \uc81c\uc57d \uc870\uac74\uc774 \uc788\ub294 \uc5f4\uc774\ub098 \ud574\ub2f9\ud558\ub294 \uc81c\uc57d \uc870\uac74 \uc5c6\uc774 \uace0\uc720 \uc778\ub371\uc2a4\uac00 \uc788\ub294 \uc5f4\uc758 \ub3d9\ub4f1 \uc220\uc5b4(Optimizer\ub294 \uc774\ub7ec\ud55c \uc220\uc5b4\uac00 \ud56d\uc0c1 \ud558\ub098\uc758 \ud589\uc744 \ubc18\ud658\ud558\uac70\ub098 \ud589\uc744 \uc804\ud600 \ubc18\ud658\ud558\uc9c0 \uc54a\ub294\ub2e4\ub294 \uc0ac\uc2e4\uc744 \uc778\uc2dd\ud568)<\/p>\n

<\/div>\n
\n
Nested Loop Join<\/span><\/div>\n

<\/b><\/div>\n
\uc120\ud589(Driving) \ud14c\uc774\ube14 \uc870\uac74\uc5d0 \ub9de\ub294 \ub370\uc774\ud130\uc640 \ub9e4\uce58\ub418\ub294 \uac12\uc744 \ub2e4\ub978(\ud6c4\ud589) \ud14c\uc774\ube14\uc5d0\uc11c \ucc38\uc870<\/div>\n
<\/div>\n
\uc218\ud589\uacfc\uc815 – TAB1\uc774 \uc120\ud589 \ud14c\uc774\ube14\uc77c \ub54c<\/div>\n
<\/div>\n
SQL> SELECT a.FLD1, …, b.FLD1,… <\/div>\n
     FROM   TAB2 b, TAB1 a<\/div>\n
     WHERE  a.KEY1 = b.KEY2 <\/div>\n
     AND    b.FLD2 like ‘A%’<\/div>\n
     AND    a.FLD1 = ’10’<\/div>\n
<\/div>\n
a.FLD1 \uc778\ub371\uc2a4 5000\uac74 Range Scan                                       <\/div>\n
rowid\ub85c TAB1\uc5d0 5000\ud68c random access<\/div>\n
\uc131\uacf5\/\uc2e4\ud328\uc5d0 \uc0c1\uad00\uc5c6\uc774 b.KEY2 \uc778\ub371\uc2a4\uc5d0 5000\ud68c random access \ubc0f \uc870\uc778\uc2dc\ub3c4<\/div>\n
\uc870\uc778\uc5d0 \uc131\uacf5\ud55c rowid\ub85c TAB2\uc5d0 100\ud68c random access<\/div>\n
b.FLD2 like ‘A%’ \uccb4\ud06c \ud6c4 \uc131\uacf5\ud55c 50\uac74 \uc6b4\ubc18\ub2e8\uc704 \uc774\ub3d9<\/div>\n
<\/div>\n
\uc218\ud589\uacfc\uc815 – TAB2\uac00 \uc120\ud589\ud14c\uc774\ube14\uc77c \ub54c<\/div>\n
<\/div>\n
SQL> SELECT a.FLD1, …, b.FLD1,… <\/div>\n
     FROM   TAB2 b, TAB1 a<\/div>\n
     WHERE  a.KEY1 = b.KEY2 <\/div>\n
     AND    b.FLD2 like ‘A%’<\/div>\n
     AND    a.FLD1 = ’10’<\/div>\n
<\/div>\n
b.FLD2 \uc778\ub371\uc2a4 100\uac74 Range Scan<\/div>\n
TAB2\uc758 100\ud68c random access<\/div>\n
\uc131\uacf5\/\uc2e4\ud328\uc5d0 \uc0c1\uad00\uc5c6\uc774 a.KEY1 \uc778\ub371\uc2a4\uc5d0 100\ud68c random access \ubc0f \uc870\uc778\uc2dc\ub3c4<\/div>\n
\uc870\uc778\uc5d0 \uc131\uacf5\ud55c rowid\ub85c TAB1\uc5d0 70\ud68c random access<\/div>\n
a.FLD1 = ’10’ \uccb4\ud06c \ud6c4 \uc131\uacf5\ud55c 50\uac74 \uc6b4\ubc18\ub2e8\uc704 \uc774\ub3d9<\/div>\n
<\/div>\n
\ud2b9\uc9d5<\/div>\n
\uc120\ud589 \ud14c\uc774\ube14\uc758 \ucc98\ub9ac\ubc94\uc704\uac00 \uc77c\ub7c9\uc744 \uacb0\uc815\ud568(\ubc29\ud5a5\uc131)<\/div>\n
\uc120\ud589 \ud14c\uc774\ube14\uc758 \uac12\uc744 \ubc1b\uc544\uc11c \ud6c4\ud589 \ud14c\uc774\ube14\uc758 \ucc98\ub9ac\ubc94\uc704\uac00 \uacb0\uc815\ub428(\uc885\uc18d\uc801)<\/div>\n
\uc8fc\ub85c random access \ubc29\uc2dd\uc73c\ub85c \ucc98\ub9ac\ub428(random access)<\/div>\n
\ud6c4\ud589 \ud14c\uc774\ube14\uc758 \uc870\uc778 \uceec\ub7fc\uc758 \uc778\ub371\uc2a4\uc758 \uc720\ubb34 \ubc0f \uc870\uac74\uc758 \uc778\ub371\uc2a4 \ucc38\uc5ec\uc758 \uc815\ub3c4\uc5d0 \ub530\ub77c \uc218\ud589\uc18d\ub3c4\uac00 \ub9ce\uc774 \ucc28\uc774 \ub0a8(\uc5f0\uacb0\uace0\ub9ac \uc0c1\ud0dc)<\/div>\n
<\/div>\n
\uc0ac\uc6a9\uae30\uc900<\/div>\n
\ubd80\ubd84\ubc94\uc704\ucc98\ub9ac\ub97c \ud558\ub294 \uacbd\uc6b0\uc5d0 \uc720\ub9ac\ud568<\/div>\n
\ucc98\ub9ac\ub7c9\uc774 \uc801\uc740 \uacbd\uc6b0\uc5d0 \uc720\ub9ac\ud568 (random access\uac00 \ub9ce\uc744 \uacbd\uc6b0 \uc218\ud589\uc18d\ub3c4\ub97c \ubcf4\uc7a5\ud560 \uc218 \uc5c6\uc73c\ubbc0\ub85c Sort Merge Join\uc774\ub098 Hash Join\uc73c\ub85c \uc720\ub3c4)<\/div>\n
\uc120\ud589 \ud14c\uc774\ube14\uc758 \uacb0\uacfc\ub97c \ubc1b\uc544\uc57c\ub9cc \ud6c4\ud589 \ud14c\uc774\ube14\uc758 \ucc98\ub9ac\ubc94\uc704\ub97c \uc904\uc77c \uc218 \uc788\ub294 \uacbd\uc6b0\uc5d0 \uc720\ub9ac\ud568 (\uc5f0\uacb0\uace0\ub9ac\uc5d0 Index\uac00 \ubc18\ub4dc\uc2dc \uc874\uc7ac\ud558\uc5ec\uc57c \ud568)<\/div>\n
\uc120\ud589 \ud14c\uc774\ube14\uc758 \ucc98\ub9ac\ubc94\uc704\uac00 \uc218\ud589\uc18d\ub3c4\uc5d0 \uc808\ub300\uc801 \uc601\ud5a5\uc744 \ubbf8\uce58\ubbc0\ub85c \ucd5c\uc801\uc758 \uc870\uc778 \uc21c\uc11c\uac00 \ub420 \uc218 \uc788\ub3c4\ub85d \uc720\ub3c4\ud574\uc57c \ud568<\/div>\n<\/div>\n
<\/div>\n
Sort <\/span>\u2013<\/span> Merge Join<\/span><\/div>\n
\n
<\/div>\n
\uc591\ucabd\ud14c\uc774\ube14\uc744 \uac01\uc790 \uc561\uc138\uc2a4\ud558\uc5ec \ucc98\ub9ac \ubc94\uc704\ub97c \uc904\uc774\uace0, \uc870\uc778\uceec\ub7fc \uc21c\uc73c\ub85c \ub370\uc774\ud130\ub97c Sort \ud6c4\uc5d0 \uc870\uc778\ud558\ub294 \ubc29\uc2dd<\/div>\n
<\/div>\n
\uc218\ud589\uacfc\uc815<\/div>\n
-a.FLD1 \uc778\ub371\uc2a4 Range Scan<\/span><\/div>\n
-rowid\ub85c TAB1\uc5d0 random access<\/div>\n
-\uc870\uc778\uceec\ub7fc\uc778 a.KEY1\ub85c SORT<\/div>\n
-b.FLD2 \uc778\ub371\uc2a4 Range Scan<\/div>\n
-rowid\ub85c TAB2\uc5d0 random access<\/div>\n
-\uc870\uc778\uceec\ub7fc\uc778 b.KEY2\ub85c SORT<\/div>\n
-\uc591\ucabd \uc9d1\ud569\uc744 Scan\ud558\uba74\uc11c a.KEY1 = b.KEY2 \uc870\uc778 \uc2dc\ub3c4<\/div>\n
-\uc131\uacf5\ud55c Row \uc6b4\ubc18\ub2e8\uc704 \uc774\ub3d9<\/div>\n<\/div>\n
<\/div>\n
\n
\ud2b9\uc9d5<\/div>\n
\uc0c1\ub300 \ud14c\uc774\ube14\ub85c\ubd80\ud130 \uacb0\uacfc \uac12\uc744 \uc81c\uacf5\ubc1b\uc9c0 \uc54a\uace0, \uc790\uc2e0\uc5d0\uac8c \uc8fc\uc5b4\uc9c4 \uc870\uac74\uc73c\ub85c\ub9cc \ucc98\ub9ac\ubc94\uc704\ub97c \uacb0\uc815\ud568(\ub3c5\ub9bd\uc801)<\/div>\n
\uac01\uc790 SORT\ud6c4\uc5d0 \uc870\uc778\ud568\uc73c\ub85c \ubd80\ubd84\ubc94\uc704 \uc544\ub2cc \uc804\uccb4\ubc94\uc704 \ucc98\ub9ac\ub97c \ud568(\uc804\uccb4\ubc94\uc704 \ucc98\ub9ac)<\/div>\n
\uc870\uc778\uc758 \uc21c\uc11c\uc5d0\ub294 \uc0c1\uad00\uc5c6\uc74c(\ubb34\ubc29\ud5a5\uc131)<\/div>\n
\uc778\ub371\uc2a4\uac00 \uc544\ub2cc \uceec\ub7fc\ub3c4 Merge\ud560 \uc791\uc5c5 \ub300\uc0c1\uc744 \uc904\uc774\ubbc0\ub85c \uc911\uc694\ud55c \uc758\ubbf8\ub97c \uac00\uc9d0<\/div>\n
\ud14c\uc774\ube14\ub85c\ubd80\ud130 \uc77d\uc744 \ub54c DB_FILE_MULTIBLOCK_READ_COUNT\ub97c \uc801\uc6a9\ud568<\/div>\n
<\/div>\n
\uc0ac\uc6a9\uae30\uc900<\/div>\n
\ucc98\ub9ac\ub7c9\uc774 \ub9ce\uac70\ub098 \uc804\uccb4\ubc94\uc704 \ucc98\ub9ac \uc2dc\uc5d0 \uc720\ub9ac\ud568(random access\uac00 \ub9ce\uc740 Nested Loop Join\uc740 \ubd88\ub9ac)<\/div>\n
\uc2a4\uc2a4\ub85c \uc790\uc2e0\uc758 \ucc98\ub9ac\ubc94\uc704\ub97c \ub9ce\uc774 \uc904\uc77c \uc218 \uc788\uc744 \ub54c \uc720\ub9ac\ud568<\/div>\n
\uc5f0\uacb0\uace0\ub9ac \uc774\uc0c1 \uc0c1\ud0dc\uc5d0 \uc601\ud5a5\uc744 \ubc1b\uc9c0 \uc54a\uc73c\ubbc0\ub85c \uc5f0\uacb0\uace0\ub9ac \uceec\ub7fc\uc744 \uc704\ud55c \uc778\ub371\uc2a4\ub97c \uc0dd\uc131\ud558\uc9c0 \uc54a\uace0\ub3c4 \uc720\uc6a9\ud558\uac8c \uc0ac\uc6a9\ud560 \uc218 \uc788\uc74c<\/div>\n
\ucc98\ub9ac\ud560 \ub370\uc774\ud130\ub7c9\uc774 \uc801\uc740 \uc628\ub77c\uc778 \uc5b4\ud50c\ub9ac\ucf00\uc774\uc158\uc5d0\uc11c\ub294 Nested Loop Join\uc774 \uc720\ub9ac\ud55c \uacbd\uc6b0\uac00 \ub9ce\uc73c\ubbc0\ub85c Sort Merge Join\uc740 \uc8fc\uc758\ud558\uc5ec \uc0ac\uc6a9\ud574\uc57c \ud568<\/div>\n<\/div>\n
<\/div>\n
<\/div>\n
Hash Join <\/span><\/div>\n

\ud574\uc281\ud568\uc218 \uae30\ubc95\uc744 \ud65c\uc6a9\ud558\uc5ec \uc870\uc778\uc744 \uc218\ud589\ud558\ub294 \ubc29\uc2dd\uc73c\ub85c \ub300\ub7c9\uc758 \ub370\uc774\ud130\ub97c \uc870\uc778\ud558\ub294\ub370 \uc8fc\ub85c \uc0ac\uc6a9\ub418\uba70 CBO\uc758 \ub3d9\uce58\uc870\uc778(equijoin)\uc5d0\uc11c\ub9cc \uac00\ub2a5<\/p>\n

<\/p>\n

\uc218\ud589\uacfc\uc815<\/p>\n

-\ub450 \ud14c\uc774\ube14 \uc911 \uc801\uc740 \ud14c\uc774\ube14\uc744 \uc120\ud589 \ud14c\uc774\ube14\ub85c \uacb0\uc815<\/p>\n

-\uc120\ud589 \ud14c\uc774\ube14\uc744 Hash Function\uc744 \uc774\uc6a9\ud558\uc5ec Hash Area\uc5d0 Hash Table\uc744 \uad6c\uc131(Build Input)<\/p>\n

-Hash Area\ub9cc\uc73c\ub85c Hash Table\uc774 \uc0dd\uc131 \uac00\ub2a5\ud558\ub2e4\uba74 \ud6c4\ud589\ud14c\uc774\ube14\uc740 \ud06c\uae30\uc5d0 \uc0c1\uad00\uc5c6\uc774 \ucc28\ub840\ub85c Hash Function\uc744 \uc774\uc6a9\ud558\uc5ec Hash Table\uacfc \uc870\uc778(Probe Input)\ud558\uba74\uc11c \uc131\uacf5\ud55c \uacb0\uacfc\uac12\uc744 \uc6b4\ubc18\ub2e8\uc704\ub85c \uc774\ub3d9<\/p>\n

-Hash Area\ub9cc\uc73c\ub85c Hash Table \uc0dd\uc131\uc774 \ubd88\ucda9\ubd84 \ud558\ub2e4\uba74 Hash Table Overflow\uac00 \ubc1c\uc0dd\ud558\uc5ec \ub370\uc774\ud130\ub97c \ub098\ub220\uc11c \uc800\uc7a5 \ud560 Partition \uc218\ub97c \uacb0\uc815(Fan-out)<\/p>\n

-\uc120\ud589 \ud14c\uc774\ube14\uc758 \uc870\uc778 \uceec\ub7fc\uacfc Select List \uceec\ub7fc\uc744 \uba54\ubaa8\ub9ac\ub85c \uc77d\uc5b4 \ub4e4\uc5ec \uccab\ubc88\uc9f8 Hash Function\uc744 \uc774\uc6a9\ud558\uc5ec Partition\uc744 Mapping\ud558\uace0, \ub450\ubc88\uc9f8 Hash Function\ub97c \uc774\uc6a9\ud558\uc5ec Hash Table \uc0dd\uc131\uc2dc \uc0ac\uc6a9 \ud560 Hash Value\ub97c \uc0dd\uc131<\/p>\n

-\uc120\ud589 \ud14c\uc774\ube14\uc758 \uc870\uc778 \uceec\ub7fc\uc758 \uc720\uc77c \uac12\ub9cc\uc73c\ub85c Bit-Vector\uc744 \uc0dd\uc131(\ucd94\ud6c4 Bit-Vector filtering\uc5d0 \uc0ac\uc6a9\ud558\uae30 \uc704\ud568)<\/p>\n

-Partition\uc5d0 \ub370\uc774\ud130\ub97c MOVE\ud558\uace0 \ucc44\uc6cc\uc9c4 Partition\uc740 \ub514\uc2a4\ud06c\ub85c \ub0b4\ub824\uac10<\/p>\n

-\uc120\ud589 \ud14c\uc774\ube14\uc774 \ubaa8\ub450 \uc77d\ud600\uc9c0\uba74 Partition \ud14c\uc774\ube14\uc744 \uc644\uc131\ud558\uace0, Partition \ud06c\uae30\uc21c\uc73c\ub85c \uc815\ub82c\ud55c \ud6c4 \uc791\uc740 Partition N\uac1c\ub97c \uba54\ubaa8\ub9ac\uc5d0 \ub85c\ub4dc<\/p>\n

-\ud6c4\ud589 \ud14c\uc774\ube14\uc744 \uc77d\uc73c\uba74\uc11c \uc870\uc778\uceec\ub7fc\uc73c\ub85c Bit-Vector\uc640 Filtering\uc5d0 \uc131\uacf5\ud558\uc600\ub2e4\uba74, \uccab\ubc88\uc9f8 Hash Function\uc73c\ub85c Partition\uc744 \uacb0\uc815\ud558\uace0, \ub450\ubc88\uc9f8 Hash Function\ub97c \uc774\uc6a9\ud558\uc5ec \uba54\ubaa8\ub9ac \uc0c1\uc5d0 \uc788\ub294 \uc120\ud589\ud14c\uc774\ube14\uacfc \uc870\uc778\ud558\uace0 \uc131\uacf5\ud558\uba74 \uc6b4\ubc18\ub2e8\uc704\ub85c \uc774\ub3d9\ud558\uace0, \ud574\ub2f9 Partition\uc774 \uba54\ubaa8\ub9ac\uc5d0 \uc874\uc7ac\ud558\uc9c0 \uc54a\ub294\ub2e4\uba74 Hash Key Value, \uc870\uc778\uceec\ub7fc, Select List\ub97c \ub514\uc2a4\ud06c\uc5d0 \uc500<\/p>\n

-\ud6c4\ud589 \ud14c\uc774\ube14\uc774 \ubaa8\ub450 \uc77d\ud600\uc9c0\uba74,Bit-Vector Filtering\uc5d0 \uc131\uacf5\ud588\uc9c0\ub9cc,\uc870\uc778\uc5d0 \uc131\uacf5\ud558\uc9c0 \ubabb\ud574 \ubbf8 \ucc98\ub9ac\ub41c \uc120\ud589 \ud30c\ud2f0\uc158\uacfc \ud6c4\ud589 \ud30c\ud2f0\uc158\uc744 \uba54\ubaa8\ub9ac\uc5d0 \uc62c\ub824 \ucc28\ub840\ub85c \ubc18\ubcf5\uc218\ud589<\/p>\n

<\/div>\n
\n
\ud2b9\uc9d5<\/div>\n
\ub2e4\ub978 \ud14c\uc774\ube14\uc758 \uacb0\uacfc \uac12\uc744 \uc81c\uacf5\ubc1b\uc9c0 \uc54a\uace0, \uc790\uc2e0\uc5d0\uac8c \uc8fc\uc5b4\uc9c4 \uc870\uac74\uc73c\ub85c\ub9cc \ucc98\ub9ac\ubc94\uc704\ub97c \uacb0\uc815\ud568(\ub3c5\ub9bd\uc801)<\/div>\n
Hash Function\uc744 \uc774\uc6a9\ud558\uc5ec mapping\ud558\ub294 \ud6c4\ud589\ud14c\uc774\ube14\uc740 \uc804\uccb4\ubc94\uc704 \ucc98\ub9ac\ub97c \ud558\uac8c \ub428(\ubc18 \ubd80\ubd84\ubc94\uc704 \ucc98\ub9ac)<\/div>\n
\uba54\ubaa8\ub9ac \uc601\uc5ed\ub9cc\uc73c\ub85c Hash Table\uc744 \uc0dd\uc131\ud560 \ub54c \ucd5c\uc801\uc758 \ud6a8\uacfc\ub97c \ub0bc \uc218 \uc788\uc73c\ubbc0\ub85c \uc801\uc740 \ud14c\uc774\ube14\uc774 \uc120\ud589\ud14c\uc774\ube14\ub85c \uc120\ud0dd\ub428<\/div>\n
Hash Function\uc744 \uc774\uc6a9\ud558\ubbc0\ub85c \uacb0\uacfc\uac12\uc758 \uc815\ub82c\uc744 \ubcf4\uc7a5 \ubc1b\uc744 \uc218 \uc5c6\uc74c<\/div>\n
<\/div>\n
\uc0ac\uc6a9\uae30\uc900<\/div>\n
\ub300\ub7c9\uc758 \ub370\uc774\ud130 access\uc2dc, \ubc30\uce58 \ucc98\ub9ac, Full Table Scan \ud558\uba74\uc11c \uc870\uc778 \ud574\uc57c \ud560 \ub54c \uc720\ub9ac\ud568<\/div>\n
\ube44\uc6a9\uc740 \ub9ce\uc774 \ub4e4\uc9c0\ub9cc \uc218\ud589\uc18d\ub3c4\ub97c \ubcf4\uc7a5\ud574\uc57c \ud558\ub294 \uc791\uc5c5\uc5d0 \uc720\uc6a9<\/div>\n
\uac00\ub2a5\ud55c \uba54\ubaa8\ub9ac \ub0b4\uc5d0\uc11c \uc791\uc5c5 \uac00\ub2a5\ud558\ub3c4\ub85d initialization Parameter\ub098 Session \uc815\ubcf4\ub97c \ubcc0\uacbd\ud558\uc5ec \uc0ac\uc6a9\ud558\ub3c4\ub85d \ud568(HASH_AREA_SIZE \ub4f1)<\/div>\n<\/div>\n
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