[hibernate-issues] [Hibernate-JIRA] Closed: (HHH-3154) Criteria API use - duplicate SQL alias might be generated for subquery

Criteria API use - duplicate SQL alias might be generated for subquery ---------------------------------------------------------------------- Key: HHH-3154 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-3154 Project: Hibernate3 Issue Type: Bug Components: query-criteria Affects Versions: 3.2.6 Reporter: Denis Mukhin Assignee: Gail Badner From org/hibernate/criterion/SubqueryExpression.java - Hibernate 3.2.6 sources: ------------------------------- private void createAndSetInnerQuery(CriteriaQuery criteriaQuery, final SessionFactoryImplementor factory) { ... //with two-deep subqueries, the same alias would get generated for //both using the old method (criteriaQuery.generateSQLAlias()), so //that is now used as a fallback if the main criteria alias isn't set String alias; if ( this.criteriaImpl.getAlias() == null ) { alias = criteriaQuery.generateSQLAlias(); } else { alias = this.criteriaImpl.getAlias() + "_"; } ... } ------------------------------- This implementation means that if DetachedCriteria (passed to SubqueryExpression constructor) created without alias explicitely specified, generated SQL alias might be duplicate of what is generated for outer query because: 1. Class org.hibernate.impl.CriteriaImpl has 2 arg constructor (entity/class name and session implementor). It creates object with alias set to "this". This constructor is used from DetachedCriteria.forEntityName(String) or DetachedCriteria.forName(Class), thus DetachedCriteria is created with not-null default alias. 2. As comment in original code says generateSQLAlias() also may return duplicate names. The simplest solution I see is to always generate there SQL alias based, for instance, on SubqueryExpression class name and increasing counter stored in static field.