> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/metabase/metabase/llms.txt
> Use this file to discover all available pages before exploring further.

# Table metadata

> Customize how Metabase displays and interprets your data

Table metadata settings control how Metabase displays and interprets your database tables and columns. These settings only affect Metabase's interface—they never modify your actual database.

<Info>
  Admin users can grant table metadata permissions to other groups, allowing them to customize how data appears in Metabase.
</Info>

## Accessing metadata settings

Table metadata settings are available in the admin panel.

<Steps>
  <Step title="Open admin settings">
    Click the **grid** icon in the upper right and select **Admin**
  </Step>

  <Step title="Go to Table Metadata">
    Click the **Table Metadata** tab
  </Step>

  <Step title="Navigate to your table">
    Use the search box or tree navigation to find your database and table
  </Step>
</Steps>

## Table settings

Customize how tables appear and behave in Metabase.

### Table name and description

<AccordionGroup>
  <Accordion title="Display name">
    Click the table name box to edit how it appears throughout Metabase. Use friendly names instead of technical database names (e.g., "Customers" instead of "dim\_customer")
  </Accordion>

  <Accordion title="Description">
    Add context about what data the table contains and when to use it. Descriptions appear in the data reference and tooltips, helping users find the right table
  </Accordion>
</AccordionGroup>

### Table visibility

Control whether tables appear in the query builder and data reference.

**To hide a table:**

1. Find the table in the left sidebar navigation
2. Click the **eye** icon next to the table name

**To hide all tables in a database:**

1. Find the database in the left sidebar
2. Click the **eye** icon next to the database name

<Warning>
  Table visibility is not a security feature. Hidden tables don't appear in the query builder, but users with SQL access can still query them with statements like `SELECT * FROM hidden_table`. For true data access control, use [data permissions](../permissions/data).
</Warning>

### Table sorting

Control the order of columns in your table:

* **Automatically**: Metabase decides the best order
* **Database order**: Matches the column order in your database
* **Alphabetically**: Sorts columns A-Z
* **Custom**: Drag and drop to arrange columns, then click "Done"

### Sync and scan operations

<CardGroup cols={2}>
  <Card title="Sync table schema" icon="rotate">
    Updates Metabase to reflect recent schema changes in your database
  </Card>

  <Card title="Scan field values" icon="magnifying-glass">
    Refreshes the values used to populate filter dropdown menus
  </Card>

  <Card title="Discard cached values" icon="trash">
    Clears cached values so Metabase fetches fresh data for filter widgets
  </Card>
</CardGroup>

For more information about sync behavior, see [Syncs and scans](../databases/sync-scan).

## Field settings

Fields (also called columns) can be extensively customized to improve how they display and function in questions.

### Field name and description

<Steps>
  <Step title="Edit display name">
    Click on the field name to change its global display name in Metabase (e.g., "auth.user" → "User")
  </Step>

  <Step title="Add description">
    Click the description box below the name to add helpful context
  </Step>
</Steps>

<Tip>
  Add descriptions when columns contain abbreviations, codes, zeroes/nulls with special meaning, or placeholder values like "9999-99-99".
</Tip>

### Field preview

Click the preview button to see sample data from a field in three views:

* **Table preview**: How the field appears in table results
* **Detail**: How the field displays in expanded record views
* **Filtering**: How the filter widget will appear for this field

### Field data properties

<AccordionGroup>
  <Accordion title="Field name (database)">
    The actual column name in your database. This cannot be changed from Metabase
  </Accordion>

  <Accordion title="Data type">
    The column's data type in your database (text, number, date, etc.). Cannot be changed directly, but you can cast to different types
  </Accordion>

  <Accordion title="Cast to specific type">
    Convert fields to different data types for Metabase's use without changing your database:

    **Text to datetime:**

    * ISO8601→Date
    * ISO8601→Datetime
    * ISO8601→Time

    **Numeric to datetime:**

    * UNIXSeconds→DateTime
    * UNIXMilliSeconds→DateTime
    * UNIXMicroSeconds→DateTime
    * UNIXNanoSeconds→DateTime

    **Text to numeric:**

    * String→Integer
    * String→Float

    **Other conversions:**

    * Float→Integer
    * Datetime→Date
  </Accordion>
</AccordionGroup>

<Note>
  Casting changes only affect how Metabase interprets the data. Your database remains unchanged. For unsupported casting options, create a SQL question or database view instead.
</Note>

### Semantic type

Semantic types add meaning to your data, enabling special features and better visualizations.

**Common semantic types:**

* **Email**: Validates email format, enables mailto: links
* **URL**: Displays as clickable links
* **Image URL**: Shows images inline
* **Currency**: Applies currency formatting
* **Category**: Enables dropdown filters
* **Entity Key/Foreign Key**: Defines relationships between tables
* **Score/Rating**: Special formatting for numeric scales

Available semantic types depend on the underlying data type. Set to "No semantic type" if none fit.

For a complete reference, see [Semantic types](./semantic-types).

## Field visibility

Control where fields appear in Metabase:

<Tabs>
  <Tab title="Everywhere">
    Default setting. Fields appear in all views and the query builder
  </Tab>

  <Tab title="Only in detail views">
    Hides the field from table results but shows it when expanding individual records. Useful for long text fields like comments

    <Note>
      Automatically applied to fields with average length over 50 characters
    </Note>
  </Tab>

  <Tab title="Do not include">
    Removes the field from the query builder and data reference. This is NOT a permissions feature—users can still access these fields via SQL

    <Warning>
      Use this for convenience, not security. For true access control, use [data permissions](../permissions/data)
    </Warning>
  </Tab>
</Tabs>

## Filtering behavior

Customize how fields behave in filter widgets.

<CardGroup cols={3}>
  <Card title="Search box" icon="magnifying-glass">
    Shows a search input with autocomplete suggestions
  </Card>

  <Card title="List of all values" icon="list-check">
    Displays a dropdown with checkboxes for all distinct values (up to 1,000)
  </Card>

  <Card title="Plain input box" icon="keyboard">
    Simple text input without autocomplete
  </Card>
</CardGroup>

### Enabling dropdown filters

If you want a dropdown filter with all values:

<Steps>
  <Step title="Set semantic type">
    Change the field's semantic type to "Category"
  </Step>

  <Step title="Change filtering option">
    Set filtering to "A list of all values"
  </Step>

  <Step title="Wait for scan">
    Metabase will scan the field and cache up to 1,000 distinct values
  </Step>
</Steps>

<Warning>
  Dropdown filters work best for fields with fewer than 1,000 distinct values. For larger datasets, use "Search box" instead.
</Warning>

## Display values

Map field values to more readable alternatives.

### Foreign key mapping

Display related information instead of IDs:

**Example:** Show product names instead of `product_id` numbers

1. Select the field containing IDs
2. Choose "Display values"
3. Select the related column to display (e.g., `products.name`)

### Custom value mapping

Map specific values to custom labels:

**Example:** Map 1, 2, 3 to "Low", "Medium", "High"

<Steps>
  <Step title="Set filtering type">
    Change filtering to "A list of all values"
  </Step>

  <Step title="Open display values">
    Select "Custom mapping" from the display values dropdown
  </Step>

  <Step title="Map each value">
    Enter display text for each value under "Mapped values"
  </Step>
</Steps>

## Field scanning

Manually trigger value scans for specific fields:

1. Navigate to the field in Table Metadata
2. Click the **Field values** button
3. Choose to scan or discard cached values

Metabase uses scanned values to populate dropdown filter menus. This doesn't affect your database—only Metabase's cache.

## Field formatting

Control how field values display in results and visualizations. Options include:

* Number formatting (decimals, separators, units)
* Date and time formats
* Currency display
* Link formatting

For detailed formatting options, see [Field formatting](./formatting).

## JSON unfolding

Extract nested data from JSON columns into separate fields for easier querying.

For information about working with JSON data, see [Working with JSON](./json-unfolding).

## Metadata permissions

By default, only admins can edit table metadata. You can grant metadata editing permissions to specific groups:

1. Go to Admin > Permissions
2. Select the group
3. Navigate to Data Permissions
4. Set "Manage table metadata" to "Yes" for specific databases

For more details, see [Manage table metadata permissions](../permissions/data#manage-table-metadata-permissions).

<Note>
  Metadata permissions allow users to change how data displays but don't grant access to data they couldn't already see.
</Note>

## Best practices

<AccordionGroup>
  <Accordion title="Use friendly display names">
    Replace technical names with business-friendly terms ("Customer" instead of "dim\_cust\_base\_v2")
  </Accordion>

  <Accordion title="Add descriptions liberally">
    Document what each table and field contains, especially for ambiguous or calculated values
  </Accordion>

  <Accordion title="Set semantic types carefully">
    Proper semantic types enable better visualizations, filtering, and data exploration
  </Accordion>

  <Accordion title="Hide unnecessary fields">
    Reduce clutter by hiding technical IDs and fields users don't need for analysis
  </Accordion>

  <Accordion title="Organize with field ordering">
    Put important fields first using custom sorting to make data exploration more intuitive
  </Accordion>

  <Accordion title="Test your changes">
    After updating metadata, build a sample question to verify fields display and filter correctly
  </Accordion>
</AccordionGroup>

## Metadata vs. permissions

Understand the difference between these two concepts:

| Feature               | Purpose              | What it controls             |
| --------------------- | -------------------- | ---------------------------- |
| **Metadata settings** | Improve data display | How data appears in Metabase |
| **Data permissions**  | Control access       | Who can view and query data  |

<Warning>
  Hiding tables or fields through metadata settings does not restrict access. Users with SQL privileges can still query hidden items. Use data permissions for true access control.
</Warning>

## Further reading

<CardGroup cols={2}>
  <Card title="Semantic types" icon="tags" href="./semantic-types">
    Complete reference for all available semantic types
  </Card>

  <Card title="Field formatting" icon="paintbrush" href="./formatting">
    Customize how values display in results
  </Card>

  <Card title="Data permissions" icon="shield" href="../permissions/data">
    Control who can access and query your data
  </Card>

  <Card title="Syncs and scans" icon="rotate" href="../databases/sync-scan">
    Understand how Metabase updates schema and values
  </Card>
</CardGroup>