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Mostly right, but don't use DBI's quote() method. Use placeholders. The quote() method should be considered private to DBI and DBD::*, because it is not needed outside DBI and DBD::*. See Re^5: Variable interpolation in a file to be read in.

Using placeholders allows DBI, DBD::whatever, and the database behind DBD::whatever to cache the SQL statement passed to prepare (and prepare_cached) and especially its parsed form. Interpreting SQL with placeholders is needed exactly once, no matter how often you execute the SQL command. Interpreting SQL polluted with actual values is required every time you execute that SQL command. So for one million inserts, you can avoid 999_999 runs of the SQL interpreter by using the results from the first interpreter run by using placeholders. Simply not running complex code in 99.9999% of all cases makes your program run faster.


Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^2: SQLite Slow insert by afoken
in thread SQLite Slow insert by mmittiga17

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