Temporary changing working directory (chdir)

https://metacpan.org/release/Cwd-Guard

Provides access to PostgreSQL databases through the DBI

https://metacpan.org/release/DBD-Pg

Provides access to SQLite3 databases through the DBI

https://metacpan.org/release/DBD-SQLite

MySQL driver for the Perl5 Database Interface (DBI)

https://metacpan.org/release/DBD-mysql

Perl5 Database Interface, required for DBD::* modules

https://metacpan.org/release/DBI

Extensible and flexible object <-> relational mapper

https://metacpan.org/release/DBIx-Class

Add contextual fetches to DBI

https://metacpan.org/release/DBIx-ContextualFetch

Pure perl persistent multi-level hash/array DBM

https://metacpan.org/release/DBM-Deep

Data::Compare - compare perl data structures

https://metacpan.org/release/Data-Compare

Pretty printing of data structures

https://metacpan.org/release/Data-Dump

Stringified perl data structures, suitable for both printing and eval

https://metacpan.org/release/Data-Dumper

Less indentation and newlines plus sub deparsing

https://metacpan.org/release/Data-Dumper-Concise

Pack and unpack big-endian IEEE754 floats and doubles

https://metacpan.org/release/Data-IEEE754

Data::JavaScript - Dump perl structures to JavaScript code

https://metacpan.org/release/Data-JavaScript

Parse and validate simple name/value option pairs

https://metacpan.org/release/Data-OptList

Pager utility for Class::DBI

https://metacpan.org/release/Data-Page

Base classes wrapping fundamental Perl data types

https://metacpan.org/release/Data-Perl

Colored pretty-print of Perl data structures and objects

https://metacpan.org/release/Data-Printer

Read multiple hunks of data out of your DATA section

https://metacpan.org/release/Data-Section

Read data from __DATA__

https://metacpan.org/release/Data-Section-Simple

Generate Globally/Universally Unique Identifiers (GUIDs/UUIDs)

https://metacpan.org/release/Data-UUID

Common data validation methods for IPs

https://metacpan.org/release/Data-Validate-IP

Gregorian calendar date calculations

https://metacpan.org/pod/Date::Calc

Perl5 module containing date manipulation routines

https://metacpan.org/release/Date-Manip

Date and time object

https://metacpan.org/release/DateTime

Mayan Long Count, Haab, and Tzolkin calendars

https://metacpan.org/release/DateTime-Calendar-Mayan

Create DateTime parser classes and objects

https://metacpan.org/release/DateTime-Format-Builder

Parse ISO8601 formats

https://metacpan.org/release/DateTime-Format-ISO8601

Convert between DateTime and RFC2822/822 formats

https://metacpan.org/release/DateTime-Format-Mail

Parse and format MySQL dates and times

https://metacpan.org/release/DateTime-Format-MySQL

Parse and format PostgreSQL dates and times

https://metacpan.org/release/DateTime-Format-Pg

Parse and format SQLite dates and times

https://metacpan.org/release/DateTime-Format-SQLite

Parse and format strp and strf time patterns

https://metacpan.org/release/DateTime-Format-Strptime

Parse and format W3CDTF datetime strings

https://metacpan.org/release/DateTime-Format-W3CDTF

Create DateTime objects with sub-second current time resolution

https://metacpan.org/release/DateTime-HiRes

Localization support for DateTime

https://metacpan.org/release/DateTime-Locale

Time zone object base class and factory

https://metacpan.org/release/DateTime-TimeZone

Declarative Validation of Perl Data Structures

https://metacpan.org/release/Declare-Constraints-Simple

Figure out the names of variables passed into subroutines

https://metacpan.org/release/Devel-ArgNames

Perl module which is meatier versions of caller

https://metacpan.org/release/Devel-Caller

Check that a command is available

https://metacpan.org/release/Devel-CheckBin

Check the compiler availability

https://metacpan.org/release/Devel-CheckCompiler

Check that a library is available

https://metacpan.org/release/Devel-CheckLib

Find memory cycles in objects

https://metacpan.org/release/Devel-Cycle

Expose PL_dirty, the flag which marks global destruction

https://metacpan.org/release/Devel-GlobalDestruction

Perl module which does alias lexical variables

https://metacpan.org/release/Devel-LexAlias

Perl Memory Analysis Tool

https://metacpan.org/release/Devel-MAT

Write a heap dump file for later analysis

https://metacpan.org/release/Devel-MAT-Dumper

Introspect overloaded operators

https://metacpan.org/release/Devel-OverloadInfo

Obtain the REFCNT value of a referent

https://metacpan.org/release/Devel-Refcount