# Error messages

This section contains information on error messages (including how to resolve the issue) you may encounter while working with Dali.

Column "<COLUMN_NAME>" cannot be resolved.

You mapped an entity's field to an incorrect or invalid column in the database table. By default, Dali will attempt to map each field in the entity with an identically named row in the database table. If the field's name differs from the row's name, you must explicitly create the mapping.

Map the field to a valid row in the database table as shown in "Mapping an entity".

Entity does not have an Id.

You created a persistent entity without identifying its primary key. A persistent entity must have a primary key field designated with an `@Id` annotation.

Add an ID mapping to the entity as shown in "ID mapping".

MappedBy specified on both sides of the "<MAPPED_FIELD>" relationship.

You selected a Mapped By database field on both the source and target of a Many-to-many mapping. This field is required only on the non-owning side of the relationship.

See "Persistence Properties view (for attributes)" for more information.

MappedBy specified on "<MAPPED_FIELD>" is not a valid mapping type.

You selected in invalid database field as the owner of a One-to-one mapping. On the General tab of the mapping, select the field in the database table that "owns" the relationship. This field is required only on the non-owning side of the relationship

See "Persistence Properties view (for attributes)" for more information.

Multiple Version properties are not allowed.

You created two version mappings for an entity. Each persistent entity may have a single Version mapping. Change the mapping type of one of the fields to a different mapping type.

See "Mapping an entity" for more information.

Table "<TABLE_NAME>" cannot be found on the database.

You associated a persistent entity to an incorrect or invalid database table. By default, Dali will attempt to associate each persistent entity with an identically named database table. If the entity's name differs from the table's name, you must explicitly create the association.

Associate the entity with a valid database table as shown in "Adding persistence to a class".

Target "<CLASS_NAME>" class is not an entity.

You created an relationship mapping from a field in an entity to a nonpersistent class. The target of OR relationship must be an entity.

Map the target class as an entity as shown in "Persistent entity". See "Mapping an entity" for more information.

The join column "<COLUMN_NAME>" cannot be found on the table.

The column that you selected to join a relationship mapping does not exist on the database table. Either select a different column on the Join Table tab or create the necessary column on the database table.

See "Persistence Properties view (for attributes)" for more information.

The referenced column "<COLUMN_NAME>" cannot be found on the table.

The column that you selected to join a relationship mapping does not exist on the database table. Either select a different column on the Join Table tab or create the necessary column on the database table.

See "Persistence Properties view (for attributes)" for more information.

The table "<TABLE_NAME>" cannot be found on the database.

You attempted to associate an entity or mapping to a table that does not exist on the database. Verify that you are connected to the database and create the specific table, if necessary.

See "Project Properties page – Persistence Options" for more information.

The table "<TABLE_NAME>" is not associated with the owning entity.

The column that you selected to join a relationship mapping is not associated with the referenced (owning) entity. You must associate each entity with a database table on the entity's General tab in the Persistence Properties view.

See "Persistence Properties view (for entities)" for more information.

Version mapping type must be int, Integer, short, Short, long, Long, or Timestamp.

For a Version mapping, the attribute must be mapped to a database column of one of a valid type, as listed in "Version mapping". See "Mapping an entity" for more information.

Version mappings must be mapped to the primary table.

For a Version mapping, the attribute must be mapped to the primary table associated with the entity. Confirm that the Column Name field of the version mapping is identical to the Table field on the entity's General tab. See "Version mapping" and "Mapping an entity" for more information.

Problems view