database - How to get a mysql query to use a specific index? - 


select * orders (index(idx));

when fired above query got error

mysql #1064 - have error in sql syntax

i have created index below

create index idx on orders(date,status);

can tell me correct syntax?

if index appropriate used without explicitly specifying it.

given using select * not expect index used (even if index hint had correct syntax). choice down query optimiser's heuristics.

the correct syntax is:

select * orders use index(idx);

ref: index hints

also, please note: 99 times out of 100, specifying index hint should not done. let optimiser job.


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