Hello Gents,
I have a few queries regarding the TOAST Fields serialisation/deserialization performance.
The use case i am trying to solve here is to have millions of partitions and aggregate the data in array field.
I wish to know if i declare certain column in table as "array of UDT/JSONB" and enable either lz4 or zstd compression on it, does appending or prepending to that array or even changing the intermediate fields of UDT/JSONB objects. in that array has a runtime cost of full array data de-serialization every single time. If i perform any UPDATE operation on its elements or add/remove new elements from any position, does PG rewrites the new version of the column value regardless of its size.
Let me know if more inputs are required
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