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豢豌: devworld.co.kr
/*+ ALL_ROWS */ explicitly chooses the cost-based approach to optimize a statement block with a goal of best throughput (that is, minimum total resource consumption) 螳 譬 豌襴 覈襦 覓 觚襦 豕蠍 cost-based 蠏 覦覯 . (讀, 豌伎 豕 觜) /*+ CHOOSE */
causes the optimizer to choose between the rule-based approach and the cost-based approach for a SQL statement based on the presence of statistics for the tables accessed by the statement 豕(optimizer)螳 蠏 覓語 蠏朱 企 糾 譟伎 蠏手碓襯 SQL 覓語 rule-based 蠏 覦覯螻 cot-based 蠏 覦覯 伎 蟆 . /*+ FIRST_ROWS */
explicitly chooses the cost-based approach to optimize a statement block with a goal of best response time (minimum resource usage to return first row) 螳 譬 螳 覈襦 覓 觚襦 豕蠍 cost-based 蠏 覦覯 . (豌覯讌 譯朱 豕 ) /*+ RULE */
explicitly chooses rule-based optimization for a statement block 覓 觚襦 , rule-based 豕襯 螻襯企 /*+ AND_EQUAL(table index) */
explicitly chooses an execution plan that uses an access path that merges the scans on several single-column indexes 蠏碁 ろ 螻 . 蠏碁Μ螻 酔 single-column 語 蠏 scan 覲 蠏 蟆暑襯 . /*+ CLUSTER(table) */
explicitly chooses a cluster scan to access the specified table . 蠏碁Μ螻, 企ろ磯 蠏 覈 企 蠏狩蠍 危. /*+ FULL(table) */
explicitly chooses a full table scan for the specified table 蠏 覈 企 , 豌 企 scan 螻襯企 /*+ HASH(table) */
explicitly chooses a hash scan to access the specified table . 蠏碁Μ螻, 伎 蠏 覈 企 蠏狩蠍 伎 危. /*+ HASH_AJ(table) */
transforms a NOT IN subquery into a hash antijoin to access the specified table 覲, 蠏 覈 企 蠏狩 伎 antijoin朱 NOT IN 覿 譟壱 /*+ HASH_SJ (table) */
transforms a NOT IN subquery into a hash anti-join to access the specified table 覲, 蠏 覈 企 蠏狩 伎 anti-join朱 NOT IN 覿 譟壱 /*+ INDEX(table index) */
explicitly chooses an index scan for the specified table 蠏 覈 企 , scan 螻襯企 /*+ INDEX_ASC(table index) */
explicitly chooses an ascending-range index scan for the specified table 蠏 覈 企 , ascending-range scan 螻襯企 /*+ INDEX_COMBINE(table index) */
If no indexes are given as arguments for the INDEX_COMBINE hint, the optimizer uses whatever Boolean combination of bitmap indexes has the best cost estimate. If particular indexes are given as arguments, the optimizer tries to use some Boolean combination of those particular bitmap indexes. 企 碁 INDEX_COMBINE 襯 語襦 譯殊伎讌 る, bitmap 語 蟆壱 企 覿語襯 螳 譬 企 螳襯 螳讌螻 讌 豕 伎. 豪 語 語襦 譯殊伎る, 豕 蠏 豪 bitmap 語 覈覈 覿語 蟆壱 り 碁ロ. /*+ INDEX_DESC(table index) */
explicitly chooses a descending-range index scan for the specified table 蠏 覈 企 , descending-range scan 螻襯企 /*+ INDEX_FFS(table index) */
causes a fast full index scan to be performed rather than a full table scan 觜襯 豌 scan 豌 企 scan企手鍵覲企る 蟆 . /*+ MERGE_AJ (table) */
transforms a NOT IN subquery into a merge anti-join to access the specified table 覲, NOT IN 覿 譟壱, 蠏 覈 企 蠏狩蠍 anti-join 覲. /*+ MERGE_SJ (table) */
transforms a correlated EXISTS subquery into a merge semi-join to access the specified table 覲, 蟯 EXISTS 覿 譟壱, 蠏殊朱 semi-join 覲, 蠏 覈 企 /*+ ROWID(table) */
explicitly chooses a table scan by ROWID for the specified table 蠏 覈 企 , ROWID 企 scan 螻襯企 /*+ USE_CONCAT */
forces combined OR conditions in the WHERE clause of a query to be transformed into a compound query using the UNION ALL set operator 讌 WHERE 覓語 UNION ALL 讌 一一襯 煙 讌襦 覲 OR 譟郁唄 豎れ給. /*+ ORDERED */
causes Oracle to join tables in the order in which they appear in the FROM clause る狩伎 企 蟆 襦 企 蟆壱り . /*+ STAR */
forces the large table to be joined last using a nested-loops join on the index 企 豕譬 / nested-loops襯 蟆壱 蠏 語 蟆壱. /*+ DRIVING_SITE (table) */
forces query execution to be done at a different site from that selected by Oracle 蠏瑚螻 るジ る狩伎 危語 ろ 讌. /*+ USE_HASH (table) */
causes Oracle to join each specified table with another row source with a hash join る狩伎 企 るジ 朱 伎 朱 覈覃伎 螳 豺蟆 . /*+ USE_MERGE (table) */
causes Oracle to join each specified table with another row source with a sort-merge join る狩伎 企 るジ 朱 sort-merge 朱 覈覃伎 螳 豺蟆 . /*+ USE_NL (table) */
causes Oracle to join each specified table to another row source with a nested-loops join using the specified table as the inner table る狩伎 蠏 覈 企 蠏 企襦 nested-loops 螻 螳 るジ 覈 企 豺蟆 . /*+ APPEND */ , /*+ NOAPPEND */
specifies that data is simply appended (or not) to a table; existing free space is not used. Use these hints only following the INSERT keyword. 一危螳 企襦 щ讌る (or not)蟆 覈; 覓企 譟危 讌 給. 讌 蠏 曙 旧企ゼ 磯ゴ 襯 . /*+ NOPARALLEL(table) */
disables parallel scanning of a table, even if the table was created with a PARALLEL clause 蠏 企 PARALLEL 覓語襦 襦 襷れ伎る 企 谿 蟆 覓企ロ蟆 襷. /*+ PARALLEL(table, instances) */
allows you to specify the desired number of concurrent slave processes that can be used for the operation. DELETE, INSERT, and UPDATE operations are considered for parallelization only if the session is in a PARALLEL DML enabled mode. (Use ALTER SESSION PARALLEL DML to enter this mode.) 轟 蠏 一一 企(slave) 襦語れ 蟲 襯 覈 蟆 渚. 蠏 語 螳ロ蟆 PARALLEL DML 覈襯 る, DELETE, INSERT, UPDATE 一一 讌 parallelization 螻る. ( 覈 れ願蠍 語 DML 覲蟆渚.) /*+ PARALLEL_INDEX
allows you to parallelize fast full index scan for partitioned and nonpartitioned indexes that have the PARALLEL attribute parallelize 轟蟆 觜襯 螳 scan 渚. 蠏碁磯, 蠏瑚 PARALLEL 煙 螳讌螻 語 覿螻 nonpartitioned給. /*+ NOPARALLEL_INDEX */
overrides a PARALLEL attribute setting on an index 覲 語 螳 蟆 蟆 豌 /*+ CACHE */
specifies that the blocks retrieved for the table in the hint are placed at the most recently used end of the LRU list in the buffer cache when a full table scan is performed 蠏 觚襦 谿場 螳語る 蟆 覈. 蠏碁Μ螻 蠏 企 蠏 讌. 蠏碁磯, 蠏瑚 螳 讀 語 蠏 覯 貂, 螳 企 scan LRU 襴ろ語 . . /*+ NOCACHE */
specifies that the blocks retrieved for this table are placed at the least recently used end of the LRU list in the buffer cache when a full table scan is performed 蠏 覈. 蠏碁Μ螻, 蠏 觚襦 企 蟆覃伎 讀 語 蠏 覯 貂, 螳 企 scan LRU 襴ろ語 螳 讌. . /*+ MERGE (table) */
causes Oracle to evaluate complex views or subqueries before the surrounding query る狩伎 蠏 碁 讌 覲旧″ 觀磯 覿 譟壱襯 螳蟆 . /*+ NO_MERGE (table) */
causes Oracle not to merge mergeable views る狩伎 mergeable 觀磯ゼ 覲讌 蟆 讌 給 /*+ PUSH_JOIN_PRED (table) */
causes the optimizer to evaluate, on a cost basis, whether or not to push individual join predicates into the view 螳螳 覩碁 蟆 蠏 觀 朱 螳 觜 覦朱 豕螳 螳蟆 . /*+ NO_PUSH_JOIN_PRED (table) */
Prevents pushing of a join predicate into the view 覿 譴 蠏 觀磯 覦覃伎, 襷 /*+ PUSH_SUBQ */
causes nonmerged subqueries to be evaluated at the earliest possible place in the execution plan 語 蠏 ろ 螻 螳 企ジ 螳ロ レ 螳 覿 譟壱襯 nonmerged給. /*+ STAR_TRANSFORMATION */
makes the optimizer use the best plan in which the transformation has been used. 豕螳 蠏 覲 螳 譬 螻
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螳 朱 蟲 豌 覺 讌朱 覦 螳襴襯 讌 . 覺 朱 覲旧蟒企 覯蟒 覿讌 . 襴 覿 ル瑚 企蟆 るジ 蟒覲企 蟆 朱 讌 . 蠏語 覓給牛 譴觜覃 願概 螻 訖企. 蠏碁り 襷る語襴 蠏語螻 讌 螳 蠍 谿襦螳 讌蠍 蟲 る 譴觜伎 蠏 リ鍵 襯 襷蟷 觸企 蟆企. (觜) |