HHH-8548 - HHH-3047 causes regressions

hibernate-core/src/main/java/org/hibernate/dialect/Dialect.java

@@ -1892,6 +1892,11 @@ public abstract class Dialect implements ConversionContext {
 
 	/**
 	 * What is the maximum length Hibernate can use for generated aliases?
+	 * <p/>
+	 * The maximum here should account for the fact that Hibernate often needs to append "uniqueing" information
+	 * to the end of generated aliases.  That "uniqueing" information will be added to the end of a identifier
+	 * generated to the length specified here; so be sure to leave some room (generally speaking 5 positions will
+	 * suffice).
 	 *
 	 * @return The maximum length.
 	 */

hibernate-core/src/main/java/org/hibernate/dialect/Oracle8iDialect.java

@@ -609,6 +609,7 @@ public class Oracle8iDialect extends Dialect {
 	
 	@Override
 	public int getMaxAliasLength() {
-		return 30;
+		// Oracle's max identifier length is 30, but Hibernate needs to add "uniqueing info" so we account for that,
+		return 20;
 	}
 }