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I have a sqlite table that has two columns: COL_A and COL_B (both integer). Now i want to select some records where col_a has values from one large (hundreds, maybe few thousands) set and col_b has values from another large set:
SELECT * FROM my_table WHERE col_1 IN (<large set of integers>) AND col_2 IN (<another large set of integers>)

This will result in error:
DBD::SQLite::db prepare_cached failed: too many SQL variables


My attempt to go around this problem resulted in this code.
use List::MoreUtils qw/natatime/; sub select_in_chunks { my ($self, $set_1, $set_2) = @_; my @ret; my $chunk_size = 450; my $it1 = natatime $chunk_size, @$set_1; while (my @a = $it1->()) { my $it2 = natatime $chunk_size, @$set_2; while (my @b = $it2->()) { # previous query with subsets my $records = $self->query(\@a, \@b) push @ret, @$records; } } return \@ret; }

This actually works but i wonder if there is a more convenient (and faster!) way to do selects with large IN statements. I can't use BETWEEN operator since those values aren't continuous.

Any ideas?

In reply to SQLite and large number of parameters by menth0l

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