explain (SELECT netdev.id,devName,ip,birthdayDate,manufacturer,sendDate,maintenanceDate,build,pp.paraName as ppname,netdev.xh as xhname,'服務器' as type,O.oname FROM netdev
left join para as pp on netdev.pp = pp.id left join organize as O on netdev.zzid=O.id where netdev.id)
union all
(SELECT s.id,subName as devName,subIp as ip,birthdayDate,manufacturer,sendDate,maintenanceDate,build,a.paraname as ppname,s.XH as xhname,'控制單元' as type,O.oname FROM subserver s left join para as a on s.PP = a.id left join organize as O on s.zzid=O.id WHERE zzid != '0' )
union all
(SELECT crossing.id,crsName as devName,crsIp as ip,birthdayDate,manufacturer,sendDate,maintenanceDate,build,pp.paraName as ppname,crossing.xh as xhname,'運維節(jié)點' as type,O.oname FROM crossing
left join para as pp on crossing.pp = pp.id left join organize as O on crossing.zzid=O.id)
union all
(SELECT cam.id,cam.cameraName as devName,cam.ip as ip,birthdayDate,p.paraName as manufacturer,sendDate,maintenanceDate,build,pp.paraName as ppname,cam.xh as xhname,'前端設備' as type,O.oname FROM camera as cam left join para as pp on cam.pp = pp.id left join crossingcamera crs on crs.cameraCode = cam.cameraCode left join para as p on cam.sdk = p.paraValue and p.paraType='manufacturer' left join organize as O on cam.zzid=O.id)
union all
(SELECT R.id,R.name as devName,R.ip,birthdayDate,manufacturer,sendDate,maintenanceDate,build,pp.paraName as ppname,R.xh as xhname,'動環(huán)設備' as type,O.oname FROM ringdev
as R left join para as pp on R.pp=pp.id left join organize as O on R.oid=O.id)
union all
(SELECT O.id,O.name as devName,O.ip,birthdayDate,manufacturer,sendDate,maintenanceDate,build,pp.paraName as ppname,O.xh as xhname,'其他設備' as type,ORG.oname FROM otherdev
as O left join para as pp on O.pp=pp.id left join organize as ORG on O.oid=ORG.id)
limit 0,20
現(xiàn)在想顯示所有設備的信息,因為最初的建表原因(建表非本人操作)... 所以用到union all
但是當某個表的數據達到10w以上查詢就變的很慢 這個應該怎么優(yōu)化?
之前因為問題不完整,可能是我想簡單了... 請各位諒解 ?。。?/p>
北大青鳥APTECH成立于1999年。依托北京大學優(yōu)質雄厚的教育資源和背景,秉承“教育改變生活”的發(fā)展理念,致力于培養(yǎng)中國IT技能型緊缺人才,是大數據專業(yè)的國家
北大青鳥中博軟件學院創(chuàng)立于2003年,作為華東區(qū)著名互聯(lián)網學院和江蘇省首批服務外包人才培訓基地,中博成功培育了近30000名軟件工程師走向高薪崗位,合作企業(yè)超4
中公教育集團創(chuàng)建于1999年,經過二十年潛心發(fā)展,已由一家北大畢業(yè)生自主創(chuàng)業(yè)的信息技術與教育服務機構,發(fā)展為教育服務業(yè)的綜合性企業(yè)集團,成為集合面授教學培訓、網
達內教育集團成立于2002年,是一家由留學海歸創(chuàng)辦的高端職業(yè)教育培訓機構,是中國一站式人才培養(yǎng)平臺、一站式人才輸送平臺。2014年4月3日在美國成功上市,融資1
曾工作于聯(lián)想擔任系統(tǒng)開發(fā)工程師,曾在博彥科技股份有限公司擔任項目經理從事移動互聯(lián)網管理及研發(fā)工作,曾創(chuàng)辦藍懿科技有限責任公司從事總經理職務負責iOS教學及管理工作。
浪潮集團項目經理。精通Java與.NET 技術, 熟練的跨平臺面向對象開發(fā)經驗,技術功底深厚。 授課風格 授課風格清新自然、條理清晰、主次分明、重點難點突出、引人入勝。
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具有10 年的Java 企業(yè)應用開發(fā)經驗。曾經歷任德國Software AG 技術顧問,美國Dachieve 系統(tǒng)架構師,美國AngelEngineers Inc. 系統(tǒng)架構師。