各位帮忙解析一下这个SQL语句!
小弟开始学写sql,简单的没有问题,现在遇到了不懂得,请赐教!
什么set nocount on/off, nolock, inner 不明白。或者有没有推荐的书可以学的
SET nocount on select distinct ll.lot, a.attributetype+'@'+ll.location+'@'+f.facility+'@'+slc.conversion+'='+a.attributevalue from lotattributes la inner join lotlocations ll (nolock) on la.lotlocn_id = ll.lotlocn_id inner join attributes a (nolock) on a.attribute_id=la.attribute_id inner join factories f (nolock) on f.factory_id = ll.factory_id inner join sumlevelconversion slc (nolock) on slc.sumlevel = la.sumlevel where lot in ('ABC') SET nocount off