Fix random_page_cost for SSD storage
random_page_cost defaults to 4.0, a spinning-disk assumption. On SSD, random reads are nearly as cheap as sequential, lowering it to ~1.1 flips a selective query from a Bitmap Heap Scan to a straight Index Scan.
Problem
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The planner weighs random vs sequential I/O using random_page_cost (default 4.0) and seq_page_cost (1.0). That 4:1 ratio reflects spinning disks. On SSD or well-cached storage random access is far cheaper, so the default makes the planner avoid index scans it should prefer.
Meridian runs on SSDs but the planner still assumes random reads are 4x sequential, so it picks a Bitmap Heap Scan on parcel_scans_rpc where a plain Index Scan would fit the hardware better.
Simple terms
The planner chooses between a random-access index scan and a straight sequential scan by comparing their costs, and by default it assumes a random read is four times as expensive as a sequential one, an assumption straight from the spinning-disk era. On SSDs random reads are almost as cheap as sequential, so that stale 4:1 ratio makes the planner shy away from index scans it should be choosing. Lowering random_page_cost to match your hardware fixes it.
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