对pl/sql 语句的优化（上集）
对这个进行优化
select n5001 门店,n5002 部门,n5004 小分类,n5019 商品编码,c01d21 商品名称,
nvl(xse,0)-nvl(dzxs,0) 销售,
mle 毛利,
nvl(xl,0)-nvl(dzsl,0) 销量
from
(select n5001,n5002,n5004,n5019,sum(n5011) xse,sum(n5016) mle,sum(n5023) xl
from n50
where to_char(n5010,'yyyymmdd')>='20100401'
and to_char(n5010,'yyyymmdd')<='20100431'
group by n5001,n5002,n5004,n5019),
(select g08,g09,g02,sum(g03*g07) dzxs,sum(G03) dzsl from batchgoods
where to_char(g04,'yyyymmdd')>='20100401'
and to_char(g04,'yyyymmdd')<='20100431'
group by g08,g09,g02),c01d
where n5001=g08(+)
and n5019=g02(+)
and n5001=c01d00(+)
and n5019=c01d01(+)
执行计划
SELECT STATEMENT, GOAL = CHOOSE Cost=10060 Cardinality=3931 Bytes=475651
MERGE JOIN OUTER Cost=10060 Cardinality=3931 Bytes=475651
SORT JOIN Cost=8063 Cardinality=3931 Bytes=338066
NESTED LOOPS OUTER Cost=7952 Cardinality=3931 Bytes=338066
VIEW Object owner=FZDC Cost=4015 Cardinality=3931 Bytes=239791
SORT GROUP BY Cost=4015 Cardinality=3931 Bytes=149378
TABLE ACCESS FULL Object owner=FZDC Object name=N50 Cost=3955 Cardinality=3931 Bytes=149378
TABLE ACCESS BY INDEX ROWID Object owner=FZDC Object name=C01D
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