Cleanup docs, implement appendHqlString for DiscriminatorSqmPath and fix MapMember type

documentation/src/main/asciidoc/userguide/chapters/domain/extras/embeddable/embeddable-type-override-mapping-example.sql

@@ -1,20 +1,20 @@
 create table Book (
     id bigint not null,
     author varchar(255),
-    ebook_publisher_name varchar(255),
-    paper_back_publisher_name varchar(255),
+    ebook_pub_name varchar(255),
+    paper_back_pub_name varchar(255),
     title varchar(255),
-    ebook_publisher_country_id bigint,
-    paper_back_publisher_country_id bigint,
+    ebook_pub_country_id bigint,
+    paper_back_pub_country_id bigint,
     primary key (id)
 )
 
 alter table Book
     add constraint FKm39ibh5jstybnslaoojkbac2g
-    foreign key (ebook_publisher_country_id)
+    foreign key (ebook_pub_country_id)
     references Country
 
 alter table Book
     add constraint FK7kqy9da323p7jw7wvqgs6aek7
-    foreign key (paper_back_publisher_country_id)
+    foreign key (paper_back_pub_country_id)
     references Country

hibernate-core/src/main/java/org/hibernate/metamodel/internal/AttributeFactory.java

@@ -589,7 +589,10 @@ public class AttributeFactory {
 		final EmbeddableDomainType<?> ownerType = (EmbeddableDomainType) attributeContext.getOwnerType();
 
 		if ( ownerType.getRepresentationStrategy().getMode() == RepresentationMode.MAP ) {
-			return new MapMember( attributeContext.getPropertyMapping().getName(), ownerType.getExpressableJavaTypeDescriptor().getJavaTypeClass() );
+			return new MapMember(
+					attributeContext.getPropertyMapping().getName(),
+					attributeContext.getPropertyMapping().getType().getReturnedClass()
+			);
 		}
 		else {
 			return ownerType.getRepresentationStrategy()

hibernate-core/src/main/java/org/hibernate/metamodel/model/domain/internal/DiscriminatorSqmPath.java

@@ -72,7 +72,9 @@ public class DiscriminatorSqmPath extends AbstractSqmPath implements SelfInterpr
 
 	@Override
 	public void appendHqlString(StringBuilder sb) {
-		// todo (6.0) : no idea
+		sb.append( "type(" );
+		getLhs().appendHqlString( sb );
+		sb.append( ')' );
 	}
 
 	@Override