功效
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R1S1 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R1S2 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R1S3 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R1S4 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R1S5 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R1S6 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R2S1 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R2S2 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R2S3 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R2S4 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R2S5 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R2S6 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R3S1 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R3S2 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
PART_ID: 1001 -Power Mac G4 Desktop -Product Type XBO31 1WAJ3B - RACK_NUM R3S3 - PART_TYPE_ID 101 - PART_TYPE_DESC MAC - edit ? delete
最佳谜底
您应该行使某些前提将表毗连在一路,譬喻：
SELECT PART_ID,PART_DESC,SERIAL_NUM,RACK_NUM,PART.PART_TYPE_ID,PART_TYPE_DESC
FROM PART
INNER JOIN PART_TYPE ON PART.PART_TYPE_ID = PART_TYPE.PART_TYPE_ID
根基上,这将实现从PART表中获取全部行,而且对付我们找到的每一行,将该行与PART_TYPE表中的行匹配(前提是它们具有沟通的PART_TYPE_ID).假如在PART表中的给定行中找不到PART和PART_TYPE表之间的匹配项,则该行不会包括在功效中.现实上,这意味着您只能得到具有有用对应零件范例的零件.
留意：行使SELECT *从表中选择全部列凡是不同意,由于它使维护变得坚苦.假如您要添加,删除或从头分列列,则全部代码城市间断.因此,我变动了您的select语句,以显式检索您引用的列,其次序与代码中引用的次序沟通.
编辑：喂授代码中省略了与RACK表的毗连,由于您没有引用RACK.LOCATION列.假如这是一个错误,只需抛出另一个毗连：
INNER JOIN RACK ON RACK.RACK_NUM = PART.RACK_NUM
并将LOCATION列添加到SELECT语句中要检索的列的列表中.
（编辑：湖南网）
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