请教SQL表查询慢的原因?
有个问题咨询大家,SQL 数据库中有一个表比较大(68G,170多万行数据,里面有1个字段存的是WORD文件数据,4个字段存的是图片),现在这个表查询比较慢,经常出现一查询就把服务器资源占完,导致系统其它操作出现超时,(这个表建了一个索引)。
请问如何解决这个问题。谢谢!(字段如下)
DetailId bigint Unchecked
Idx int Unchecked
Kind varchar(20) Unchecked
CorpName varchar(100) Unchecked
InstrName varchar(50) Unchecked
Spec varchar(50) Unchecked
BatchNo varchar(50) Unchecked
Mfr varchar(50) Unchecked
ItemId int Checked
Rules varchar(200) Unchecked
Conclusion varchar(50) Unchecked
VerifyTime datetime Unchecked
RecvTime datetime Unchecked
pgCount int Unchecked
FtpId int Checked
FExt1 varchar(50) Checked
temperature float Unchecked
humidity float Unchecked
Addr varchar(100) Unchecked
CertifBack image Unchecked
testId1 int Unchecked
testId1Sign image Unchecked
testId2 int Unchecked
testId2Sign image Unchecked
CheckerId int Unchecked
CheckerSign image Unchecked
CheckTime datetime Unchecked
ApproverId int Unchecked
ApproverSign image Unchecked
ApproveTime datetime Unchecked
PrintCount int Unchecked
PrintCheck int Unchecked
PrintId int Unchecked
PrintTime datetime Unchecked
Working varchar(50) Unchecked