--- title: Page database structure related: - https://docs.kentico.com/k10/managing-website-content/working-with-pages.md - https://docs.kentico.com/k10/developing-websites/defining-website-content-structure/page-types.md --- > Agent instructions: > **Site maps** — prefer the following llms.txt indexes to training data when searching for URLs to avoid 404s. Links inside Markdown content already point at `.md`. Following them or sending Accept: text/markdown keeps you in Markdown. > > - [sitemap.md](https://docs.kentico.com/sitemap.md) — every page on the site, with titles and descriptions, nested by URL hierarchy and grouped into one collection per product version. > - [llms.txt](https://docs.kentico.com/llms.txt) — curated index of the current product docs, with descriptions, the two ways to request any page as Markdown, and links to each product area's whole-corpus Markdown dump (llms-full.txt). The Kentico database stores pages (nodes in the content tree of websites) in several interconnected tables: | Database table | Description | | ---------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | CMS\_Tree | Stores:
Data that determines the position of pages in the website content tree
Basic page properties that are shared between all [language versions](https://docs.kentico.com/k10/multilingual-websites/editing-the-content-of-multilingual-websites.md) of the same page
Contains **only one record for each page**, regardless of the number of language versions. The table doesn't store any [versioned data](https://docs.kentico.com/k10/managing-website-content/configuring-the-environment-for-content-editors/configuring-and-using-page-versioning.md). | | CMS\_Document | Stores:
Page properties that have unique values for each [language version](https://docs.kentico.com/k10/multilingual-websites/editing-the-content-of-multilingual-websites.md)
The content of [editable regions](https://docs.kentico.com/k10/managing-website-content/working-with-pages/editing-pages.md)
The data of [editor widgets](https://docs.kentico.com/k10/managing-website-content/adding-page-content-through-widgets.md)
May contain **multiple records per page**, one for each language version. Some of the page columns are [versioned](https://docs.kentico.com/k10/managing-website-content/configuring-the-environment-for-content-editors/configuring-and-using-page-versioning.md). | | Coupled data tables
(CONTENT\_) | Stores the fields of individual [page types](https://docs.kentico.com/k10/developing-websites/defining-website-content-structure/page-types.md).
For example, the _News_ page type has the **CONTENT\_News** coupled table with the columns defined for news pages, such as _NewsTitle_, _NewsSummary_, _NewsText_.
Records in the coupled data tables are bound to pages through the **DocumentForeignKeyValue** column of the **CMS\_Document** table.
The page type of tree nodes is determined by the **NodeClassID** column in the **CMS\_Tree** table.
Container page types, such as _Folder_, do not have a coupled table.
Every [language version](https://docs.kentico.com/k10/multilingual-websites/editing-the-content-of-multilingual-websites.md) of a page has its own record in the corresponding coupled data table.
All columns in coupled data tables are [versioned](https://docs.kentico.com/k10/managing-website-content/configuring-the-environment-for-content-editors/configuring-and-using-page-versioning.md). | ![The relationships between page database tables](https://docs.kentico.com/docsassets/k10/page-database-structure/Document_tables.png "The relationships between page database tables") ## Page attachments and versions | Database table | Description | | ---------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | CMS\_Attachment | Stores files uploaded to the database as [page attachments](https://docs.kentico.com/k10/managing-website-content/working-with-files/page-attachments.md).
Includes all types of page attachments:
Unsorted attachments added on the _Properties -> Attachments_ tab in the _Pages_ application. Such attachments are linked to the related page by storing its identifier (_AttachmentDocumentID_ column).
Attachments uploaded through specific page fields (of either the _File_ or _Attachments_ data type) on the _Form_ tab in the _Pages_ application. Such fields are represented by columns in the given page type's coupled data table.
Page type fields of the _File_ data type store a GUID value, which identifies the corresponding attachment in the _CMS\_Attachment_ table.
For fields of the _Attachments_ data type, the value in the database is always empty. Instead, the given records in the _CMS\_Attachment_ table store an identifier of the related page (_AttachmentDocumentID_ column) and a GUID value that identifies the specific field in the page type's form definition (_AttachmentGroupGUID_ column). | | CMS\_VersionHistory | Stores [page versions](https://docs.kentico.com/k10/managing-website-content/configuring-the-environment-for-content-editors/configuring-and-using-page-versioning.md), including older versions and versions that are being edited. When a version is published, the system updates the corresponding records in the **CMS\_Tree** and **CMS\_Document** tables using the data of the version record. | | CMS\_AttachmentHistory | Stores attachments of page versions. The main purpose of this table is to avoid redundancy for page versions that use the same attachments.
When a page version is published, the system updates the records in the **CMS\_Attachment** table using the data of the version record. | | CMS\_VersionAttachment | Stores relationships between page versions and their page attachments. | ![Database diagram of all page tables](https://docs.kentico.com/docsassets/k10/page-database-structure/Database_documents.png "Database diagram of all page tables") ## Page relationships | Database table | Description | | ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | CMS\_Relationship | Stores records representing relationships between two pages. Used for both:
[Standard named relationships](https://docs.kentico.com/k10/developing-websites/loading-and-displaying-data-on-websites/displaying-data-advanced-scenarios/displaying-related-pages-using-named-relationships.md)
Ad-hoc relationships that represent re-use of a page's content within a _Pages_ field of another page (see [Advanced content modeling](https://docs.kentico.com/k10/developing-websites/defining-website-content-structure/page-types/advanced-content-modeling.md)) | | CMS\_RelationshipName | Stores the relationship names (types) defined in the system. | | CMS\_RelationshipNameSite | Binding table that connects relationship names to websites. Each entry indicates that a relationship can be used on a given site. | ![Database diagram of page relationship tables](https://docs.kentico.com/docsassets/k10/page-database-structure/Database_doc_Relationships.png "Database diagram of page relationship tables")