internal override void _generateRowQualifierFromContext(PipeHdfContext ctx, PipeRowQualifier rob)
{
QualifierBase qual = ctx.getQualifier(this.context_key);
if (qual != null) {
rob.appendKeyPart(qual);
} else {
throw new PipeGenerateException(this, "missing context: " + this.context_key);
}
this.next_stage._generateRowQualifierFromContext(ctx, rob);
}