这是一查询数据库表的SQL源码,请教擅长者帮忙优化一下in下的语句
select distinct (specreal.speciality_id)
from om_datarole_spec_rela_t specreal,
om_funcrole_relation_t funreal,
OM_SYS_ROLE_T sysrole,
OM_ROLE_PERSON_RELA_T sysreal,
OM_DATAROLE_DISTRICT_RELA_T DISRELA
WHERE specreal.data_role_sno = sysrole.data_role_sno
and sysrole.fun_role_sno = funreal.fun_role_sno
and funreal.f_id = 'B'
AND SYSROLE.DATA_ROLE_SNO = DISRELA.DATA_ROLE_SNO
and sysrole.sys_role_sno = sysreal.sys_role_sno
and sysreal.f_employee_id = '00003502'
and specreal.speciality_id [color=red]in/color))
[b]问题补充:[/b]
这是在Oracle环境下的,业务逻辑可以对应字段!多谢。
[b]问题补充:[/b]
谢了,第一此执行速度于优化前速度,第二次执行却快于优化前第二次执行很多?我再看一下,下午确认一下,多谢了O(∩_∩)O哈哈~