SELECT FROM order table WHERE order date | | order time < = "20180725180000"AND type =" "AND status =" "AND ROWNUM < *;
how to optimize the sql to speed up the query efficiency.
SELECT FROM order table WHERE order date | | order time < = "20180725180000"AND type =" "AND status =" "AND ROWNUM < *;
how to optimize the sql to speed up the query efficiency.
create an index on the order date
Thesql statement is modified slightly:
select *
from (
SELECT * FROM WHERE < '20180726' AND = '' AND = ''
)
where < '20180725' or ( = '20180725' and <= '180000')
and rownum < 10other aspects can only be considered from the hardware point of view, put the data files corresponding to the order table on the SSD hard drive.
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