REFRESH VIRTUAL COLUMN
Introduced or updated: v1.2.271
VIRTUAL COLUMN is an Enterprise Edition feature. Contact Databend Support for a license.
Refreshes virtual columns for a table. Virtual columns needs refreshing in the following scenarios:
- After creating virtual columns for a table that already contains Variant data, it is necessary to refresh the virtual columns.
- When modifying virtual columns for a table, refresh them after the modifications.
- If the
enable_refresh_virtual_column_after_writesetting is set to 1 (default), virtual columns for a table are automatically refreshed after data updates. However, if this setting is not enabled, manual refreshing of virtual columns becomes necessary.
Syntax
REFRESH VIRTUAL COLUMN FOR <table>
Examples
This example refreshes virtual columns for a table named 'test':
REFRESH VIRTUAL COLUMN FOR test;