As part of my application I calculate/generate a fair chunk of data, and
I then stick the reults into the database (mysql). This takes the form
of a single "INSERT INTO foo(…) VALUES(…) " statement that is approx
~500k
The dats itself consists of pairs of integers.
If I dump the query string to disk and paste it into the query browser
and run it then execution is <1 second.
If however I do ActiveRecord::Base.connection.execute sql_statement
then it takes 50 odd seconds to run. During this time cpu load is close
to nothing.
Any ideas on what could be causing this slow down?