-- 89_drop_dead_brin_rosreestr_deals.sql
-- DROP dead BRIN index per code-review audit (2026-05-14).
--
-- Context: rosreestr_deals_period_brin was created on the partitioned parent
-- table, but PG16 does NOT propagate BRIN indexes to child partitions.
-- The parent table holds zero rows (all data lives in child partitions).
-- Queries are pruned via the partition key (period_start_date) directly —
-- the BRIN index is never consulted.
-- pg_stat_user_indexes.idx_scan = 0 for this index confirms zero usage.
-- Note: DB connection was unavailable at migration creation time (SSH tunnel
-- down). idx_scan=0 inferred from PG16 behaviour + no manual BRIN usage
-- in any query in the codebase. Verify with SELECT below before applying.
--
-- Verification (run before applying):
--   SELECT idx_scan FROM pg_stat_user_indexes
--   WHERE indexrelname = 'rosreestr_deals_period_brin';
--   -- Expected: 0
--
--   SELECT tablename FROM pg_indexes
--   WHERE indexname = 'rosreestr_deals_period_brin';
--   -- Expected: 'rosreestr_deals' (parent only, no child rows)
--
-- Source: data/sql/01_schema_rosreestr_deals.sql line 66-67 (original CREATE)
-- Apply order: after all 88_* migrations have been applied
-- Dependencies: rosreestr_deals partitioned table must exist
--
-- Rollback: re-create per-partition if range scan optimisation is ever needed
--   (partition pruning is sufficient for the current query patterns;
--    measure with EXPLAIN ANALYSE before deciding to re-create)
--
--   Example per-partition rollback:
--   CREATE INDEX rosreestr_deals_2025q1_period_brin
--       ON rosreestr_deals_2025q1 USING BRIN (period_start_date);
--   -- repeat for each partition

BEGIN;

DROP INDEX IF EXISTS rosreestr_deals_period_brin;

COMMIT;
