---
schema_version: "1"
id: b671cae0da1694ba08e45036fbacc55c55a3b8b7b16c6111a5c4c89c1772bc57
title: About Data Policies
collection: tableau
version: current
locale: en-gb
portal_url: https://docs.salesforce.com/tableau/current/en-gb/server-linux/ipa_vconn_about_data_policy.md
canonical_url: https://help.tableau.com/current/server-linux/en-gb/ipa_vconn_about_data_policy.htm
source_site: help.tableau.com
content_type: documentation
content_hash: c3fd0f917d819747a487ed9bdb1678802b78f71e0de4148c409c496b1181bef4
description: Quick help on data policies that apply row-level security in a virtual connection.
---
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# About Data Policies

Use a data policy when you want to apply row-level security to one or more tables in the connection. Data policies apply to both live and extract connections.

A data policy has three main components:

![An example of the three components of a data policy](/tableau/current/en-gb/server-linux/en-gb/Img/ipa_vconns_policy_components.png)

1. The tables they apply to are called policy tables. These are the tables that are filtered.
2. The mapped columns that define the relationships between tables (for example, between entitlement and fact tables) and between table columns and policy columns. A policy column is the column used to filter data.
3. The policy condition, which is an expression that is evaluated for every row at query time. When TRUE, the row is shown in the query.

To get started, click ![Create New Policy button](/tableau/current/en-gb/server-linux/en-gb/Img/ipa_Create_New_Policy_btn.png).

[Read full topic](https://help.tableau.com/current/server-linux/en-gb/dm_vconn_create_rlspolicy.htm)

## Related tasks

[About the Virtual Connection Editor](https://help.tableau.com/current/server-linux/en-gb/ipa_vconn_about_editor.htm)

[Add Tables to the Connection](https://help.tableau.com/current/server-linux/en-gb/ipa_vconn_add_tables.htm)

[Create and Test Data Policies](https://help.tableau.com/current/server-linux/en-gb/ipa_vconn_create_data_policy.htm)

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