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>)

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

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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;
    }

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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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