# 37.63. view\_column\_usage

The view `view_column_usage` identifies all columns that are used in the query expression of a view (the `SELECT` statement that defines the view). A column is only included if the table that contains the column is owned by a currently enabled role.

#### Note

Columns of system tables are not included. This should be fixed sometime.

#### **Table 37.61. `view_column_usage` Columns**

| <p>Column Type</p><p>Description</p>                                                                                                                                                               |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <p><code>view\_catalog</code> <code>sql\_identifier</code></p><p>Name of the database that contains the view (always the current database)</p>                                                     |
| <p><code>view\_schema</code> <code>sql\_identifier</code></p><p>Name of the schema that contains the view</p>                                                                                      |
| <p><code>view\_name</code> <code>sql\_identifier</code></p><p>Name of the view</p>                                                                                                                 |
| <p><code>table\_catalog</code> <code>sql\_identifier</code></p><p>Name of the database that contains the table that contains the column that is used by the view (always the current database)</p> |
| <p><code>table\_schema</code> <code>sql\_identifier</code></p><p>Name of the schema that contains the table that contains the column that is used by the view</p>                                  |
| <p><code>table\_name</code> <code>sql\_identifier</code></p><p>Name of the table that contains the column that is used by the view</p>                                                             |
| <p><code>column\_name</code> <code>sql\_identifier</code></p><p>Name of the column that is used by the view</p>                                                                                    |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.postgresql.tw/16/client-interfaces/the-information-schema/view_column_usage.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.