Connecting to the Database Perl

database, mysql, performance, perl

Solution

In the line:

@row= $sqlQuery->fetchrow_array();

One row ata time will be returned by the database to perl, if interacting with a massive database you will not dump the entire result set of the query to a variable.

$arrRef = $sqlQuery->fetchall_arrayref();

On the other hand..

Problem

I am connecting to a mysql database using the following code: ``` my $dbh = DBI->connect("DBI:mysql:test:localhost", $user, $pass) or die $DBI::errstr; my $sqlQuery = $dbh->prepare($query) or die "Can't prepare $query: $dbh->errstr\n"; my $rv = $sqlQuery->execute or die "can't execute the query: $sqlQuery->errstr"; while (my @row= $sqlQuery->fetchrow_array()) { # do something; } ``` My doubt is: It is fine till the time my application is interacting with small DBs. But when I move this application to a live environment where the DB size may be in 100s of GBs, what performance issues can this code cause. Effectively what I am asking is, at the line - ``` @row= $sqlQuery->fetchrow_array(); ``` Will Perl copy the entire table contents and dump it into the variable. If yes, won't it cause significant performance issues for my application as well as the database server?

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