Overview

Enhanced TOAST is a technology used to process oversized fields. First, it reduces redundant information in the TOAST pointer so that more than 500 columns of oversized fields can be stored in a single table. Second, it optimizes the mapping between main tables and out-of-line storage tables so that the pg_toast_index table does not need to store such relationship, reducing user storage space. Lastly, the enhanced TOAST technology eliminates the dependency on OID allocation. Instead, it allows split data to be automatically linked, greatly improving write efficiency.

• The Astore storage engine does not support enhanced TOAST.
• No VACUUM FULL operation can be separately performed on out-of-line storage tables of the enhanced TOAST type.