Clinton and folks will probably give you a more correct answer, but here's mine in the meantime.
1) iBatis Java uses the JDBC API to access databases. In other words, any database that has a JDBC driver should be compatible. Concerning the SQL itself, since the programmer is responsible for building/managing the SQL, it is then your job to make it compatible with whatever database you're dealing with. Personally, I work with iBatis on MySQL and I've heard others speak of Oracle, PostgreSQL and also DB2. 2) It is difficult to compare iBatis to these tools. Let me clarify what iBatis is not: it is NOT an Object/Relational Mapping (ORM) tool nor is it a persistence engine. In other words, it does not map Objects to Relational DB tables. You can use iBatis to accomplish ORM or persistence, but it is not its goal. Hence comparing it to these tools would not be of great value. iBatis is a "SQL Result mapping" framework. It helps you dynamically build complex SQL statements using objects as input and allows you to "map" the result back into complex object models. SQL statements are built using an XML format, similar to JSP tags. 3) Since iBatis is not a persistence engine, it is your responsibility to manage queries that create/update rows in a database. There is no answer to your question as it depends on your implementation. It is up to you to determine what your priorities are and implement them using the framework. iBatis SQLMaps has no restrictions about how you should use it. It simply creates SQL statements from objects and maps SQL results to objects. In other words, you can build your own ORM solution that fits you particular needs if that is what you require. As an example, my use of the iBatis framework allows me to have a single statement that can update a single row or multiple rows in a table based on the state of the object being updated. By looking at the state of the object, the resulting SQL UPDATE statement can modify many columns or a single one. Also, using the same paradigm, I'm able to build complex queries that "JOIN" on different tables depending on the object that describes a search criteria. The same SQL Map could JOIN on any number of tables depending on its input object. Hope this helps, Philippe Laflamme -----Original Message----- From: Oliver Zeigermann [mailto:[EMAIL PROTECTED] Sent: Monday, November 29, 2004 12:21 PM To: [EMAIL PROTECTED] Subject: A few dumb questions Folks, I am considering to use ibatis as a database mapping tool for Jakarta Slide and am wondering if anyone can tell me 1) which databases are known to work with ibatis? Really all known ones? Or this there an explicite list? 2) how ibatis compares to OBJ (http://db.apache.org/ojb) or hibernate? What would be reasons for ibatis? 3) if I store back a huge object which is only partly changed, how does ibatis know which data to store back? Does it compare the object to anything? Is caching involved in this? Or does it store back everything? Would be great if anyone had any hints! Cheers and thanks in advance, Oliver
