hibernate/hibernate-orm · error · IllegalStateException

Multiple MemberMapping defined for simple identifier mapping

Error message

Multiple MemberMapping defined for simple identifier mapping : {}

What it means

Error "Multiple MemberMapping defined for simple identifier mapping : {}" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/query/results/internal/jpa/EntityBuilder.java:266

			final boolean isId = idMapping.getAttributeName().equals( memberMapping.name() );
			if ( isId ) {
				setIdMapping( memberMapping );
			}
			return isId;
		}

		@Override
		public boolean handleMember(EmbeddedMapping<?, ?> memberMapping) {
			final boolean isId = idMapping.getAttributeName().equals( memberMapping.name() );
			if ( isId ) {
				setIdMapping( memberMapping );
			}
			return isId;
		}

		private void setIdMapping(MemberMapping<?> memberMapping) {
			if ( this.memberMapping != null ) {
				throw new IllegalStateException( "Multiple MemberMapping defined for simple identifier mapping : " + entityDescriptor.getEntityName() );
			}
			this.memberMapping = memberMapping;
		}

		@Override
		public FetchBuilder buildFetchBuilder() {
			if ( memberMapping instanceof FieldMapping<?,?> basicMapping ) {
				return new CompleteFetchBuilderBasicPart(
						rootPath.append( basicMapping.name() ),
						idMapping.asBasicValuedModelPart(),
						basicMapping.columnName()
				);
			}
			else if ( memberMapping instanceof EmbeddedMapping<?,?> embeddedMapping ) {
				return new CompleteFetchBuilderEmbeddableValuedModelPart(
						rootPath.append( embeddedMapping.name() ),
						idMapping.asEmbeddedAttributeMapping(),
						extractColumnNames( embeddedMapping, idMapping.asEmbeddedAttributeMapping() )

View on GitHub (pinned to fad1729dce)

Solutions

1. Multiple member mappings were defined for a simple identifier. Keep exactly one mapping for a simple id.

When it happens

Trigger: A JPA result mapping for an embedded/identifier attribute is invalid: Multiple MemberMapping defined for simple identifier mapping : <value>

Common situations: @SqlResultSetMapping/@MappingElement definitions referencing non-embedded attributes, missing column names, or duplicate member mappings.

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/82ffa6bdac3f64c3. Report an issue: GitHub.