addNotNullConstraint

The addNotNullConstraint Change Type adds a NOT NULL constraint to an existing table.

Uses

You can typically use the addNotNullConstraint Change Type when you want to apply a NOT NULL constraint value to a specific table instead of having nullable columns in that table. The addNotNullConstraint Change Type enforces a column to always contain a value and not to accept NULL values so that you cannot insert or update a record without adding a value to the column containing this constraint.

If a defaultNullValue attribute is passed, all null values for the column will be updated to the passed value before the constraint is applied. If null values exist in your database, and if you don’t not use a defaultNullValue attribute, the change will fail.

Running the addNotNullConstraint Change Type

To add a NOT NULL constraint to your table, follow these steps:

  1. Add the addNotNullConstraint Change Type to your changeset with the needed attributes as it is shown in the examples.
  2. Deploy your changeset by running the update command:
    liquibase update

Available attributes

Name Description Required for Supports
catalogName

Name of the catalog

 all
columnDataType

Data type of the column.

To help make scripts database-independent, Liquibase automatically converts the following generic data types to the correct database implementation: BIGINT, BLOB, BOOLEAN, CHAR, CLOB, CURRENCY, DATE, DATETIME, DECIMAL, DOUBLE, FLOAT, INT, MEDIUMINT, NCHAR, NUMBER, NVARCHAR, SMALLINT, TIME, TIMESTAMP, TINYINT, UUID, VARCHAR, XML.

Also, specifying a java.sql.Types.* type is converted to the correct type as well. For example:

  • java.sql.Types.TIMESTAMP
  • java.sql.Types.VARCHAR(255)
informix, mariadb, mssql, mysql all
columnName Name of the column for which to add the constraint. all all
constraintName Name of the constraint to add (if database supports names for NOT NULL constraints) --
defaultNullValue

The value for which you can set all values that currently equal null in a column. If null values exist and if defaultNullValue is not set, the change will fail.

 all
schemaName

Name of the schema

 all
tableName Name of the table to add a NOT NULL constraint to. If a defaultNullValue attribute is passed, all null values for the column will be updated to the passed value before the constraint is applied. all all
validate

Set to true if the constraint has ENABLE VALIDATE set, or false if the constraint has ENABLE NOVALIDATE set.

 all 
...
<changeSet author="liquibase-docs"  id="addNotNullConstraint-example">  
    <addNotNullConstraint catalogName="cat"
           columnDataType="int"  
           columnName="id"  
           constraintName="const_name"  
           defaultNullValue="A String"  
           schemaName="public" 
           tableName="person"  
           validate="true"/> 
</changeSet>
...
...
-  changeSet:  
    id:  addNotNullConstraint-example  
    author:  liquibase-docs  
    changes:  
    -  addNotNullConstraint:  
        catalogName:  cat  
        columnDataType:  int  
        columnName:  id  
        constraintName:  const_name  
        defaultNullValue:  A String  
        schemaName:  public  
        tableName:  person  
        validate:  true
...
...
{
  "changeSet":{
     "id":"addNotNullConstraint-example",
     "author":"liquibase-docs",
     "changes":[
        {
           "addNotNullConstraint":{
              "catalogName":"cat",
              "columnDataType":"int",
              "columnName":"id",
              "constraintName":"const_name",
              "defaultNullValue":"A String",
              "schemaName":"public",
              "tableName":"person",
              "validate":true
           }
        }
     ]
  }
}
...
...
--changeset liquibase-docs:addNotNullConstraint-example
UPDATE cat.person SET id = 'INT' WHERE id IS NULL; 
ALTER TABLE cat.person MODIFY id INT NOT NULL;
...

Database support

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