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spread_min_analysis

ʹÓÃÕâÒ»hint£¬Äã¿ÉÒÔºöÂÔһЩ¹ØÓÚÈçÏêϸµÄ¹ØϵÒÀÀµÍ¼·ÖÎöµÈµç×Ó±í¸ñµÄ±àÒëʱ¼äÓÅ»¯¹æÔò¡£ÆäËûµÄһЩÓÅ»¯£¬Èç´´½¨¹ýÂËÒÔÓÐÑ¡ÔñÐԵĶ¨Î»µç×Ó±í¸ñ·ÃÎʽṹ²¢ÏÞÖÆÐÞ¶©¹æÔòµÈ£¬µÃµ½Á˼ÌÐøʹÓá£
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SELECT /*+ SPREAD_MIN_ANALYSIS */ ...
spread_no_analysis

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SELECT /*+ SPREAD_NO_ANALYSIS */ ...
use_nl_with_index

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ÖУ¬Ëü²ÅʹÓÃÌض¨±í¸ñ×÷ΪÄÚ²¿±í¸ñ:Èç¹ûûÓÐÖ¸¶¨±êÇ©£¬CBO±ØÐë¿ÉÒÔʹÓÃһЩ±êÇ©£¬ÇÒÕâЩ±êÇ©ÖÁÉÙÓÐÒ»¸ö×÷ΪË÷Òý¼üÖµ¼ÓÈëÅжÏ;·´Ö®£¬CBO±ØÐëÄܹ»Ê¹
ÓÃÖÁÉÙÓÐÒ»¸ö×÷ΪË÷Òý¼üÖµ¼ÓÈëÅжϵıêÇ©¡£
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SELECT /*+ USE_NL_WITH_INDEX (polrecpolrind) */ ...
CARDINALITY

´Ëhint¶¨ÒåÁ˶ÔÓɲéѯ»ò²éѯ²¿·Ö·µ»ØµÄ»ùÊýµÄÆÀ¼Û¡£×¢ÒâÈç¹ûûÓж¨Òå±í¸ñ£¬»ùÊýÊÇÓÉÕû¸ö²éѯËù·µ»ØµÄ×ÜÐÐÊý¡£
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SELECT /*+ CARDINALITY ( [tablespec] card ) */
SELECTIVITY

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SELECT /*+ SELECTIVITY ( [tablespec] sel ) */
È»¶ø£¬×¢ÒâÈç¹ûhints CARDINALITY ºÍ SELECTIVITY¶¼¶¨ÒåÔÚͬÑùµÄÒ»Åú±í¸ñ£¬¶þÕ߶¼»á±»ºöÂÔ¡£
no_use_nl

Hint no_use_nlʹCBOÖ´ÐÐÑ­»·Ç¶Ì×£¬Í¨¹ý°ÑÖ¸¶¨±í¸ñ×÷ΪÄÚ²¿±í¸ñ£¬°Ñÿ¸öÖ¸¶¨±í¸ñÁ¬½Óµ½ÁíһԭʼÐС£Í¨¹ýÕâÒ»hint£¬Ö»ÓÐhash joinºÍsort-merge joins»áΪָ¶¨±í¸ñËù¿¼ÂÇ¡£
 
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SELECT /*+ NO_USE_NL ( employees ) */ ...
no_use_merge

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SELECT /*+ NO_USE_MERGE ( em


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ÕÆÎÕµÄOracle¶¨Ê±ÈÎÎñ

 Ò»¡¢ÔÚPLSQLÖд´½¨±í£º
 
create table HWQY.TEST
(
CARNO VARCHAR2(30),
CARINFOID NUMBER
)
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create or replace procedure pro_test
AS
carinfo_id number;
BEGIN
select s_CarInfoID.nextval into carinfo_id
from dual;
insert into test(test ......

OracleµÄÌåϵ

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Oracleѧϰ±Ê¼Çժ¼3

 ¡¶1¡·DDLÓï¾ä(Êý¾Ý¶¨ÒåÓïÑÔ) Data Define Language
   create
   alter
   drop
   truncate ¿ªÍ·µÄÓï¾ä truncate table <±íÃû>
      Ìصã:<1>½¨Á¢ºÍÐÞ¸ÄÊý¾Ý¶ÔÏó
         &nb ......
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