// Looks at all tables involved in all the mappings in the definition and returns a list of output keys that will be created. It will also deal with mapped
// outputs. The outputs from each mapping will only be included if it passes the inclusion/exclusion criteria based on the context. If the schema has StagingOutputs
// defined, then the calulated output list is exactly the same as the schema output list.
// @param schema a StagingSchema
// @param context a context of values used to to check mapping inclusion/exclusion
// @return a Set of unique output keys
public HashSet <String> getOutputs(StagingSchema schema, Dictionary <String, String> context)
{
HashSet <String> outputs = new HashSet <String>();
// if outputs are defined in the schema, then there is no reason to look any further into the mappings; the output defines exactly what keys will
// be returned and it doesn't matter what context is passed in that case
if (schema.getOutputMap() != null)
{
foreach (KeyValuePair <String, IOutput> entry in schema.getOutputMap())
{
outputs.Add(entry.Key);
}
return(outputs);
}
// if outputs were not defined, then the tables involved in the mappings will be used to determine the possible outputs
if (schema.getMappings() != null)
{
foreach (StagingMapping mapping in schema.getMappings())
{
outputs.UnionWith(getOutputs(mapping, context));
}
}
// if valid outputs are defined on the schema level, only return outputs that defined; this removed "temporary" outputs that may be defined during the
// staging process
if (schema.getOutputMap() != null)
{
outputs.RemoveWhere(entry => !schema.getOutputMap().ContainsKey(entry));
}
return(outputs);
}
