SQL Projection is the collective name for the columns that are Selected and returned from a query. In other words, the columns goes behind select in a query. In Oracle, a whole row is first fetched, then data values from the columns within that row are extracted into the known projection.
To see the projection in SQL Developer, go to "Tools" --> "Preferences" --> "Database" --> "Autotrace/Explain Plan", select "projection".
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