Question: Is there any perl modules implementing function of database and easy to use. I do not need modules used to connect to some database products. I need simple database writing by perl.

Thanks.

Answer: 
I would suggest using [DBD::SQLite](https://metacpan.org/pod/DBD::SQLite). This is a self-contained database management system with no dependency to external binaries (unlike most others DBI drivers). It has nice options such as creating in-memory databases.

[SQLite](https://www.sqlite.org/index.html) is an open-source RDBMS that implements a significant subset of the SQL ANSI Standard.

`DBD::SQLite` is a legitimate DBI driver, so it conforms to the API of the great [DBI module](https://metacpan.org/pod/DBI), which is the de-facto Perl standard interface for databases.

From the documentation:

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> DBD::SQLite is a Perl DBI driver for SQLite, that includes the entire thing in the distribution. So in order to get a fast transaction capable RDBMS working for your perl project you simply have to install this module, and **nothing** else.
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If you can live without SQL and relations, give [DBM::Deep](https://metacpan.org/pod/distribution/DBM-Deep/lib/DBM/Deep.pod) a try. Easiest of all, I wouldn't use it in production environment for sure, but it is ideal for rapid prototyping.

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> DESCRIPTION
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> A unique flat-file database module, written in pure perl. True multi-level hash/array support (unlike MLDBM, which is faked), hybrid OO / tie() interface, cross-platform FTPable files, ACID transactions, and is quite fast. Can handle millions of keys and unlimited levels without significant slow-down. Written from the ground-up in pure perl -- this is NOT a wrapper around a C-based DBM. Out-of-the-box compatibility with Unix, Mac OS X and Windows.
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