postgresql - Translate postgres VARCHAR query into ruby activerecord -

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i need translate following postgresql query activerecord ruby query.

select *  my_table  (my_time between '2010-12-27 00:00:00' , '2011-01-28 00:00:00')    , (my_time::time)::varchar '12:00:00.%';

this pulls out 12:00:00.% piece of data each day. can time range part, don't know how translate second half of query.

thanks

you use to_char convert timestamp appropriate string form , strip off fractional seconds @ same time:

where to_char(my_time, 'hh24:mm:ss') = '12:00:00' ...

the activerecord version of pretty simple:

mytable.where("to_char(my_time, 'hh24:mm:ss') = '12:00:00'")

then chain in existing between check.

you use extract check each time component separately:

where extract(hour   my_time) = 12   , extract(minute my_time) =  0   , extract(second my_time) =  0   ...

the activerecord version of be:

mytable.where('extract(hour   my_time) = ?', 12)        .where('extract(minute my_time) = ?',  0)        .where('extract(second my_time) = ?',  0)

you'd have ask explain see version works best.


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