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Class::DBI::Iterator(3) - User Contributed Perl Documentation

📖 NAME

Class::DBI::Iterator - Iterate over Class::DBI search results

🚀 Quick Reference

Use Case	Command	Description
🔍 Searching	my $it = My::Class->search(...)	Execute search in scalar context to get an iterator
🔢 Counting	$it->count	Get the number of results
🏁 First result	$it->first	Retrieve the first result
🔄 Iterating	while ($it->next) { ... }	Loop through results one at a time
✂️ Slicing	$it->slice(10,19)	Get a range of results (list or arrayref)
🔄 Reset	$it->reset	Reset the iterator to the beginning
🗑️ Delete all	$it->delete_all	Delete all results from the database

🔍 SYNOPSIS

               my $it = My::Class->search(foo => 'bar');

               my $results = $it->count;

               my $first_result = $it->first;
               while ($it->next) { ... }

               my @slice = $it->slice(10,19);
               my $slice = $it->slice(10,19);

               $it->reset;

               $it->delete_all;

📝 DESCRIPTION

Any Class::DBI search (including a has_many method) which returns multiple objects can be made to return an iterator instead simply by executing the search in scalar context.

Then, rather than having to fetch all the results at the same time, you can fetch them one at a time, potentially saving a considerable amount of processing time and memory.

⚠️ CAVEAT

Note that there is no provision for the data changing (or even being deleted) in the database inbetween performing the search and retrieving the next result.

perl v5.32.0 2020-12-28 Class::DBI::Iterator(3pm)

📖 NAME 🚀 Quick Reference 🔍 SYNOPSIS 📝 DESCRIPTION ⚠️ CAVEAT