Re: Changing database schemas at runtime

[Lawrence Gerstley]

This worked great. Thanks for the tip.

    public boolean setDataMapSchema(DataMap dataMap, String schema) {
        try {
            for (DbEntity dbEntity : dataMap.getDbEntities()) {
                dbEntity.setSchema(schema);
            }
        } catch (Exception e) {
            System.out.println(e.toString());
            return false;
        }
        return true;
    }

Lawrence


On Jan 5, 2009, at 11:11 PM, Andrus Adamchik wrote:

Hi Lawrence,

Yeah, the "default schema" is ignored in runtime, and only per DbEntity schema is consulted. Looking back, it would've been better to use the default if DbEntity schema is not set, and we may change the behavior at some point, but for now "default schema" is only used by the Modeler.

So to change schema you would need to iterate through all DbEntities and set it per entity.

Andrus

On Jan 6, 2009, at 3:57 AM, Lawrence Gerstley wrote:

Hello,

I've been using Cayenne and allowing for changing backends at runtime--representing the same schema in MySQL, Oracle, Apache Derby, and have had success changing the backend with:

          DataSource dataSource = new PoolManager(
                  jdbcDriverDetails.getDriverClass(),
                  myURL,
                  1,
                  5,
                  myUser,
                  myPassword);

Configuration config = Configuration.getSharedConfiguration();

          DataDomain domain = config.getDomain();
          DataNode node = domain.getNode("MyDomain");
          node.setDataSource(dataSource);

My problem is that I need to also allow a user to select the schema that the datamap should be applied to. For example, in Oracle, the same schema design might be in multiple instances (in my example, KTMI3D, KTMI3M, KTMI3X, etc.). I can change these with the modeler and have it work, but I need to change it at runtime. I've tried changing it with:

          dataMap.setDefaultSchema(schema);

But haven't had much luck changing at runtime. Is there some way to do this with my approach, or is there a better approach to take if you want to switch back-ends multiple time at runtime?

Thanks for reading,

Lawrence