dropUniqueConstraint

Drops an existing unique constraint.

Note: For OracleDB, the index associated with the constraint is also dropped.

Run dropUniqueConstraint

To run this Change Type, follow these steps:

1. Add the Change Type to your changeset, as shown in the examples on this page.
2. Specify any required attributes. Use the table on this page to see which ones your database requires.
3. Deploy your changeset by running the update command:

liquibase update

Available attributes

Examples

--liquibase formatted sql

--changeset liquibase-docs:dropUniqueConstraint-example
ALTER  TABLE  cat.person  DROP  KEY  const_name;

databaseChangeLog:
-  changeSet:
    id:  dropUniqueConstraint-example
    author:  liquibase-docs
    changes:
    -  dropUniqueConstraint:
        catalogName:  cat
        constraintName:  const_name
        schemaName:  public
        tableName:  person
        uniqueColumns:  name

{
    "databaseChangeLog": [
        {
            "changeSet": {
                "id": "dropUniqueConstraint-example",
                "author": "liquibase-docs",
                "changes": [
                    {
                        "dropUniqueConstraint": {
                            "catalogName": "cat",
                            "constraintName": "const_name",
                            "schemaName": "public",
                            "tableName": "person",
                            "uniqueColumns": "name"
                        }
                    }
                ]
            }
        }
    ]
}

<databaseChangeLog
    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
    xmlns:pro="http://www.liquibase.org/xml/ns/pro"
    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
        http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd
        http://www.liquibase.org/xml/ns/dbchangelog-ext
        http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd
        http://www.liquibase.org/xml/ns/pro
        http://www.liquibase.org/xml/ns/pro/liquibase-pro-latest.xsd">

    <changeSet  author="liquibase-docs"  id="dropUniqueConstraint-example">
        <dropUniqueConstraint  catalogName="cat"
            constraintName="const_name"
            schemaName="public"
            tableName="person"
            uniqueColumns="name"/>
    </changeSet>

</databaseChangeLog>

Database support