此sql查询获取记录总共需要9分钟。。
select top 1 checkdate from BTHI1 where CUSTOMERID = 'AUTOMO' and recordtype='T' order by checkdate desc
还有其他方法可以减少查询时间吗?
zrfyljdw1#
对于此查询:
select top 1 checkdate from BTHI1 where CUSTOMERID = 'AUTOMO' and recordtype = 'T' order by checkdate desc
你想要索引吗 BTH1(CUSTOMERID, recordtype, checkdate DESC) . 前两列可以是任意顺序。请注意,您也可以这样写:
BTH1(CUSTOMERID, recordtype, checkdate DESC)
select max(checkdate) from BTHI1 where CUSTOMERID = 'AUTOMO' and recordtype = 'T';
1条答案
按热度按时间zrfyljdw1#
对于此查询:
你想要索引吗
BTH1(CUSTOMERID, recordtype, checkdate DESC)
. 前两列可以是任意顺序。请注意,您也可以这样写: