EXPLAIN - Sort

Description:

Takes data from a child node and produces sorted output, using either memory if available (depending on the work_mem setting) or “spilling” to disk. This is obviously necessary if the output needs to be sorted, though sometimes the input can be scanned in an already-sorted manner instead—e.g., if scanning a btree index compatible with the desired sort order.

Important Fields:

• Sort Method
• Sort Key
• Sort Space Type
• Sort Space Used