markUnused
Note: This is a Liquibase Pro Change Type, so you need a Liquibase Pro License Key to use it.
The markUnused
Change Type is an Oracle-specific Change Type that marks a column as unused. The markUnused
Change Type helps to avoid database slowdowns caused by dropping a populated column.
Uses
You can typically use the markUnused
Change Type to mark columns as unused rather than dropping them immediately, which allows you to decide the best time to drop those columns.
Available attributes
Name | Description | Required for | Supports |
---|---|---|---|
catalogName
|
Name of the catalog |
all | |
columnName
|
Name of the column |
all | all |
schemaName
|
Name of the schema |
all | |
tableName
|
Name of the table |
all | all |

...
<changeSet author="liquibase-docs" id="markUnused-example">
<pro:markUnused catalogName="cat"
columnName="id"
schemaName="public"
tableName="person"/>
</changeSet>
...

...
- changeSet:
id: markUnused-example
author: liquibase-docs
changes:
- markUnused:
catalogName: cat
columnName: id
schemaName: public
tableName: person
...

...
{
"changeSet": {
"id": "markUnused-example",
"author": "liquibase-docs",
"changes": [{
"markUnused": {
"catalogName": "cat",
"columnName": "id",
"schemaName": "public",
"tableName": "person"
}
}]
}
}
...

...
--changeset liquibase-docs:markUnused-example
ALTER TABLE cat.person SET UNUSED COLUMN id;
...
Database support
Database | Notes | Auto Rollback |
---|---|---|
DB2/LUW | Not Supported | No |
DB2/z | Not Supported | No |
Derby | Not Supported | No |
Firebird | Not Supported | No |
H2 | Not Supported | No |
HyperSQL | Not Supported | No |
INGRES | Not Supported | No |
Informix | Not Supported | No |
MariaDB | Not Supported | No |
MySQL | Not Supported | No |
Oracle | Supported | No |
PostgreSQL | Not Supported | No |
Snowflake | Not Supported | No |
SQL Server | Not Supported | No |
SQLite | Not Supported | No |
Sybase | Not Supported | No |
Sybase Anywhere | Not Supported | No |