There were a few issues in your code. I fixed them below.
my $sth = $dbh->prepare("INSERT INTO HLDdata (Data) VALUES (?)"); my $count = $dbh->prepare( "select count(*) from HLDdata where Data = +?"); foreach $txt (@TXT) { print "$txt\n"; open(IN,"$txt") || warn("cant open $txt"); while(<IN>){ $line = $_; $count->execute($line); my ($data) = $count->fetchrow(); print "$data \n"; if ($data != 0){ print "record exist not adding\n"; Logit("record exist not adding"); next; } my ($Data) = $line; $sth->execute($Data); $line =~s/\|/\t/g; # print "$line\n"; print OUT $line; } }
Yes, you're probably correct that the checking is taking the most of the time. This is because you're missing an index on HLDdata (data) -- sqlite has to scan the whole table every time you check for a row's existence. You can create the missing index with CREATE UNIQUE INDEX HLDdata_uniq ON HLDdata (Data);
There's a trade-off: you'll now use double the disk space. If $Data tends to be big (above a hundred bytes or so), you are better off storing a hash (sha1, md5, or similar) of $Data in the table in a second column and checking for its existence instead. (SQLite does not appear to have support for functional indices or a hashing function, so you'll have to do it on the Perl side.)
In reply to Re^4: SQLite Slow insert
by Anonymous Monk
in thread SQLite Slow insert
by mmittiga17
| For: | Use: | ||
| & | & | ||
| < | < | ||
| > | > | ||
| [ | [ | ||
| ] | ] |