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:
    4. liquibase update

Available attributes

Name Description Required for Supports Since
catalogName

Name of the catalog

 all 3.0
constraintName

Name of the constraint

 all all
schemaName

Name of the schema

 all
tableName Name of the table to drop the unique constraint from all all
uniqueColumns

For SAP SQL Anywhere, a list of columns in the UNIQUE clause

 sybase

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

Database Notes Auto Rollback
DB2/LUW Supported No
DB2/z Supported No
Derby Supported No
Firebird Supported No
Google BigQuery Supported No
H2 Supported No
HyperSQL Supported No
INGRES Supported No
Informix Supported No
MariaDB Supported No
MySQL Supported No
Oracle Supported No
PostgreSQL Supported No
Snowflake Supported No
SQL Server Supported No
SQLite Not Supported No
Sybase Supported No
Sybase Anywhere Supported No