Load Operation Phases
Load operations have two phases:
Acquisition Phase - Data from the input stream is transmitted to the AMPs. The AMPs 'acquire' the data.
The acquisition phase is not complete until all data sources are exhausted and all
data rows are on the appropriate AMPs. The data is not yet sorted or blocked, and
therefore, is not yet accessible.
Application Phase - Data is sorted, blocked, and put into its final format. All activity in this phase
is AMP-local. Data is accessible after the completion of this phase.