diff --git a/src/main/java/org/springframework/data/r2dbc/core/DefaultStatementMapper.java b/src/main/java/org/springframework/data/r2dbc/core/DefaultStatementMapper.java
index 39c91c7..1d10c7b 100644
--- a/src/main/java/org/springframework/data/r2dbc/core/DefaultStatementMapper.java
+++ b/src/main/java/org/springframework/data/r2dbc/core/DefaultStatementMapper.java
@@ -192,15 +192,15 @@ class DefaultStatementMapper implements StatementMapper {
 		BindMarkers bindMarkers = this.dialect.getBindMarkersFactory().create();
 		Table table = Table.create(updateSpec.getTable());
 
+		if (updateSpec.getUpdate() == null || updateSpec.getUpdate().getAssignments().isEmpty()) {
+			throw new IllegalArgumentException("UPDATE contains no assignments");
+		}
+
 		BoundAssignments boundAssignments = this.updateMapper.getMappedObject(bindMarkers,
 				updateSpec.getUpdate().getAssignments(), table, entity);
 
 		Bindings bindings;
 
-		if (boundAssignments.getAssignments().isEmpty()) {
-			throw new IllegalStateException("UPDATE contains no assignments");
-		}
-
 		bindings = boundAssignments.getBindings();
 
 		UpdateBuilder.UpdateWhere updateBuilder = StatementBuilder.update(table).set(boundAssignments.getAssignments());
diff --git a/src/test/java/org/springframework/data/r2dbc/core/DefaultDatabaseClientUnitTests.java b/src/test/java/org/springframework/data/r2dbc/core/DefaultDatabaseClientUnitTests.java
index efd05b6..9281ab3 100644
--- a/src/test/java/org/springframework/data/r2dbc/core/DefaultDatabaseClientUnitTests.java
+++ b/src/test/java/org/springframework/data/r2dbc/core/DefaultDatabaseClientUnitTests.java
@@ -15,6 +15,7 @@
  */
 package org.springframework.data.r2dbc.core;
 
+import static org.assertj.core.api.Assertions.*;
 import static org.mockito.Mockito.*;
 import static org.springframework.data.r2dbc.query.Criteria.*;
 
@@ -37,6 +38,7 @@ import org.mockito.junit.MockitoJUnitRunner;
 import org.reactivestreams.Publisher;
 import org.reactivestreams.Subscription;
 
+import org.springframework.data.annotation.Id;
 import org.springframework.data.r2dbc.dialect.PostgresDialect;
 import org.springframework.data.r2dbc.mapping.SettableValue;
 import org.springframework.data.r2dbc.support.R2dbcExceptionTranslator;
@@ -352,4 +354,23 @@ public class DefaultDatabaseClientUnitTests {
 				.expectNextCount(1) //
 				.verifyComplete();
 	}
+
+	@Test // gh-250
+	public void shouldThrowExceptionForSingleColumnObjectUpdate() {
+
+		DefaultDatabaseClient databaseClient = (DefaultDatabaseClient) DatabaseClient.builder()
+				.connectionFactory(connectionFactory) //
+				.dataAccessStrategy(new DefaultReactiveDataAccessStrategy(PostgresDialect.INSTANCE)) //
+				.build();
+
+		assertThatIllegalArgumentException().isThrownBy(() -> databaseClient.update() //
+				.table(IdOnly.class) //
+				.using(new IdOnly()) //
+				.then()).withMessageContaining("UPDATE contains no assignments");
+	}
+
+	static class IdOnly {
+
+		@Id String id;
+	}
 }