-- Cygnus PostgreSQL index migration
-- Derived from matrix.sql, nimble.qry, Visit MIS, and Dashboard functions/views.
--
-- IMPORTANT
-- 1. Run each CREATE INDEX as a separate statement. Do not wrap this file in BEGIN/COMMIT.
-- 2. CREATE INDEX CONCURRENTLY minimizes blocking but still consumes CPU, I/O and disk.
-- 3. Run during a lower-traffic window and monitor replication lag and free disk space.
-- 4. IF NOT EXISTS checks the name only. Run the preflight query first to inspect equivalent indexes.
-- 5. These statements do not change table columns, constraints, or stored data.

-- ---------------------------------------------------------------------------
-- Preflight: current sizes and existing definitions
-- ---------------------------------------------------------------------------

SELECT
    n.nspname AS schema_name,
    t.relname AS table_name,
    i.relname AS index_name,
    pg_size_pretty(pg_relation_size(i.oid)) AS index_size,
    pg_get_indexdef(i.oid) AS definition
FROM pg_index x
JOIN pg_class t ON t.oid = x.indrelid
JOIN pg_class i ON i.oid = x.indexrelid
JOIN pg_namespace n ON n.oid = t.relnamespace
WHERE n.nspname = 'public'
  AND t.relname IN (
      'riskalerts', 'belt_allocation', 'portfolio_branch', 'main',
      'main_operations', 'temp_reporting'
  )
ORDER BY t.relname, i.relname;

SELECT
    relname,
    n_live_tup,
    n_dead_tup,
    seq_scan,
    seq_tup_read,
    idx_scan,
    pg_size_pretty(pg_total_relation_size(relid)) AS total_size
FROM pg_stat_user_tables
WHERE relname IN (
    'riskalerts', 'belt_allocation', 'portfolio_branch', 'main',
    'main_operations', 'temp_reporting'
)
ORDER BY pg_total_relation_size(relid) DESC;

-- ---------------------------------------------------------------------------
-- Phase 1: high-confidence join and filter indexes
-- ---------------------------------------------------------------------------

-- visit_mis/current_visit_mis join riskalerts using both columns. The dump has
-- separate uuid and visit indexes, which do not provide this composite lookup.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_riskalerts_uuid_visit
    ON public.riskalerts USING btree (uuid, visit);

-- colony_allocation is a view joining colony to belt_allocation by belt_id.
-- Only belt_allocation(verifier_id) exists in the supplied schema.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_belt_allocation_belt_verifier
    ON public.belt_allocation USING btree (belt_id, verifier_id);

-- portfolio_bank_branch expands through portfolio_branch. These support its
-- joins and the common portfolio/isactive lookup used by nimble.qry.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_portfolio_branch_portfolio_active
    ON public.portfolio_branch USING btree (portfolio_id, isactive, portbranch_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_portfolio_branch_bank_branch
    ON public.portfolio_branch USING btree (bank_branch_id);

-- Dashboard hourly_tobesolved_cases filters on tobesolvedon and then reads
-- sdone/sdoneon. The existing temp_reporting indexes cover uuid and isclosed.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_temp_reporting_tobesolvedon_open
    ON public.temp_reporting USING btree (tobesolvedon)
    INCLUDE (sdone, sdoneon, portfolio_id)
    WHERE tobesolvedon IS NOT NULL;

-- scan_mis and Dashboard read today's completed scans. This avoids scanning all
-- main_operations rows having the same low-cardinality sdone value.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_operations_scan_doneon
    ON public.main_operations USING btree (sdoneon, sdoneby, uuid)
    WHERE sdone = 1 AND sdoneon IS NOT NULL;

-- Visit MIS expands residence/office/property separately. These partial indexes
-- remove deleted/non-applicable rows before branch/verifier matching. They also
-- retain uuid for the main_operations join.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_visit_res_branch_verifier
    ON public.main USING btree (branch_id, resiverifier, uuid)
    WHERE isdeleted = 0 AND rv = 1;

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_visit_off_branch_verifier
    ON public.main USING btree (branch_id, offverifier, uuid)
    WHERE isdeleted = 0 AND ov = 1;

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_visit_prop_branch_verifier
    ON public.main USING btree (branch_id, propverifier, uuid)
    WHERE isdeleted = 0 AND pv = 1;

-- vervisitmis queries verifier_monthly_data by verifier and receivedate. These
-- are partial and therefore smaller than unrestricted composite indexes.
CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_monthly_res_verifier_date
    ON public.main USING btree (resiverifier, receivedate)
    WHERE isdeleted = 0 AND rv = 1 AND sradd = 0;

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_monthly_off_verifier_date
    ON public.main USING btree (offverifier, receivedate)
    WHERE isdeleted = 0 AND ov = 1 AND soadd = 0;

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_main_monthly_prop_verifier_date
    ON public.main USING btree (propverifier, receivedate)
    WHERE isdeleted = 0 AND pv = 1 AND spadd = 0;

-- ---------------------------------------------------------------------------
-- Phase 2: foreign-key support indexes
-- ---------------------------------------------------------------------------
-- These do not directly solve Visit MIS/Dashboard latency. They prevent child
-- table scans during parent updates/deletes and support related joins.

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_case_documents_uuid
    ON public.case_documents USING btree (uuid);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_contact_mapping_contact_id
    ON public.contact_mapping USING btree (contact_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_contacts_history_contact_id
    ON public.contacts_history USING btree (contact_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_document_data_uuid
    ON public.document_data USING btree (uuid);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_field_mapping_field_id
    ON public.field_mapping USING btree (field_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_field_mapping_template_id
    ON public.field_mapping USING btree (template_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_field_value_field_id
    ON public.field_value USING btree (field_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_onlinecasedetails_uuid
    ON public.onlinecasedetails USING btree (uuid);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_options_mapping_opt_value_id
    ON public.options_mapping USING btree (opt_value_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_permission_page_id
    ON public.permission USING btree (page_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_phoneno_history_uuid
    ON public.phoneno_history USING btree (uuid);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_tagdoc_history_docid
    ON public.tagdoc_history USING btree (docid);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_tagged_docs_uuid
    ON public.tagged_docs USING btree (uuid);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_template_mapping_portfolio_id
    ON public.template_mapping USING btree (portfolio_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_template_mapping_template_id
    ON public.template_mapping USING btree (template_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_tracker_template_mapping_portfolio
    ON public.tracker_template_mapping USING btree (portfolio_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_tracker_template_mapping_tracker
    ON public.tracker_template_mapping USING btree (tracker_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_tracker_sheet_layout_sheet
    ON public.tracker_template_sheet_layout USING btree (sheet_id);

CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_tracker_template_sheets_tracker
    ON public.tracker_template_sheets USING btree (tracker_id);

-- Refresh planner statistics after all builds. ANALYZE does not rewrite tables,
-- but it consumes resources, so run it after the index builds at low traffic.
ANALYZE public.riskalerts;
ANALYZE public.belt_allocation;
ANALYZE public.portfolio_branch;
ANALYZE public.temp_reporting;
ANALYZE public.main_operations;
ANALYZE public.main;

-- ---------------------------------------------------------------------------
-- Postflight validation
-- ---------------------------------------------------------------------------

SELECT
    indexrelname,
    idx_scan,
    idx_tup_read,
    idx_tup_fetch,
    pg_size_pretty(pg_relation_size(indexrelid)) AS index_size
FROM pg_stat_user_indexes
WHERE indexrelname LIKE 'idx_%'
  AND relname IN (
      'riskalerts', 'belt_allocation', 'portfolio_branch', 'main',
      'main_operations', 'temp_reporting'
  )
ORDER BY relname, indexrelname;

-- Check for invalid indexes left by an interrupted concurrent build.
SELECT n.nspname, c.relname AS index_name
FROM pg_index i
JOIN pg_class c ON c.oid = i.indexrelid
JOIN pg_namespace n ON n.oid = c.relnamespace
WHERE n.nspname = 'public'
  AND NOT i.indisvalid;

-- ---------------------------------------------------------------------------
-- Emergency rollback reference -- intentionally commented out
-- ---------------------------------------------------------------------------
-- Uncomment and run only the index that must be removed. Do not execute this
-- section after a successful migration unless a measured regression occurs.
--
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_riskalerts_uuid_visit;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_belt_allocation_belt_verifier;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_portfolio_branch_portfolio_active;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_portfolio_branch_bank_branch;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_temp_reporting_tobesolvedon_open;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_operations_scan_doneon;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_visit_res_branch_verifier;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_visit_off_branch_verifier;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_visit_prop_branch_verifier;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_monthly_res_verifier_date;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_monthly_off_verifier_date;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_main_monthly_prop_verifier_date;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_case_documents_uuid;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_contact_mapping_contact_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_contacts_history_contact_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_document_data_uuid;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_field_mapping_field_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_field_mapping_template_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_field_value_field_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_onlinecasedetails_uuid;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_options_mapping_opt_value_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_permission_page_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_phoneno_history_uuid;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_tagdoc_history_docid;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_tagged_docs_uuid;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_template_mapping_portfolio_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_template_mapping_template_id;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_tracker_template_mapping_portfolio;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_tracker_template_mapping_tracker;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_tracker_sheet_layout_sheet;
-- DROP INDEX CONCURRENTLY IF EXISTS public.idx_tracker_template_sheets_tracker;