---
name: "MongoDB::ReadConcern"
section: "3pm"
platform: "linux"
package: "libmongodb-perl"
version: "2.2.2-3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/MongoDB::ReadConcern"
---

# MongoDB::ReadConcern(3pm)

Encapsulate and validate a read concern

## NAME

MongoDB::ReadConcern - Encapsulate and validate a read concern

## VERSION

version v2.2.2

## SYNOPSIS

```
    $rc = MongoDB::ReadConcern->new(); # no defaults
    $rc = MongoDB::ReadConcern->new(
        level    => 'local',
    );
```

## DESCRIPTION

A Read Concern describes the constraints that MongoDB must satisfy when reading data.  Read Concern was introduced in MongoDB 3.2.

## ATTRIBUTES

### level

The read concern level determines the consistency level required of data being read.

The default level is `"undef"`, which means the server will use its configured default.

If the level is set to "local", reads will return the latest data a server has locally.

Additional levels are storage engine specific.  See Read Concern \<http://docs.mongodb.org/manual/search/?query=readConcern\> in the MongoDB documentation for more details.

This may be set in a connection string with the the `"readConcernLevel"` option.

## AUTHORS

- •

  David Golden \<david@mongodb.com\>

- •

  Rassi \<rassi@mongodb.com\>

- •

  Mike Friedman \<friedo@friedo.com\>

- •

  Kristina Chodorow \<k.chodorow@gmail.com\>

- •

  Florian Ragwitz \<rafl@debian.org\>

## COPYRIGHT AND LICENSE

This software is Copyright (c) 2020 by MongoDB, Inc.

This is free software, licensed under:

```
  The Apache License, Version 2.0, January 2004
```