Understanding Query iterator

Post date: Nov 17, 2014 1:8:52 AM

The gpperfmon database iterators_* tables store information about query plan iterators and their metrics. A query iterator refers to a node or operation in a query plan. Here are the list of all possible iterators in a query on Greenplum Database instance. The iterator tables include the metric name, the column in the iterators_* table in the gpperfmon database where the metric appears, how the metric is measured (unit), and a description of the metric. The following iterators are listed: