markdown/reference/hawq-reference.html.md.erb

---
title: HAWQ Reference
---

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This section provides a complete reference to HAWQ SQL commands, management utilities, configuration parameters, environment variables, and database objects.

-   **[Server Configuration Parameter Reference](../reference/HAWQSiteConfig.html)**

    This section describes all server configuration guc/parameters that are available in HAWQ.

-   **[HDFS Configuration Reference](../reference/HDFSConfigurationParameterReference.html)**

    This reference page describes HDFS configuration values that are configured for HAWQ either within `hdfs-site.xml`, `core-site.xml`, or `hdfs-client.xml`.

-   **[Environment Variables](../reference/HAWQEnvironmentVariables.html)**

    This topic contains a reference of the environment variables that you set for HAWQ.

-   **[Character Set Support Reference](../reference/CharacterSetSupportReference.html)**

    This topic provides a referene of the character sets supported in HAWQ.

-   **[Data Types](../reference/HAWQDataTypes.html)**

    This topic provides a reference of the data types supported in HAWQ.

-   **[SQL Commands](../reference/SQLCommandReference.html)**

    This section contains a description and the syntax of the SQL commands supported by HAWQ.

-   **[System Catalog Reference](../reference/catalog/catalog_ref.html)**

    This reference describes the HAWQ system catalog tables and views.

-   **[The hawq\_toolkit Administrative Schema](../reference/toolkit/hawq_toolkit.html)**

    This section provides a reference on the `hawq_toolkit` administrative schema.

-   **[HAWQ Management Tools Reference](../reference/cli/management_tools.html)**

    Reference information for command-line utilities available in HAWQ.