#!/bin/bash
# Monitor kilat: satu skrip, empat angka kunci database aktif.
# Semua query sengaja dicakup ke database ini (current_database())
# agar hasilnya tidak tercampur aktivitas database lain.
set -euo pipefail

echo "== Server menerima koneksi? =="
pg_isready -h "$PGHOST" -p "$PGPORT"

echo "== Koneksi klien database ini / batas server =="
psql -X -At -c "SELECT (SELECT count(*)
                        FROM pg_stat_activity
                        WHERE datname = current_database()
                          AND backend_type = 'client backend')
                      || '/' || current_setting('max_connections');"

echo "== Rasio cache hit database ini =="
psql -X -At -c "SELECT round(100.0 * blks_hit
                             / nullif(blks_hit + blks_read, 0), 1) || '%'
                FROM pg_stat_database
                WHERE datname = current_database();"

echo "== Baris mati tabel penjualan_harian =="
psql -X -At -c "SELECT n_dead_tup
                FROM pg_stat_user_tables
                WHERE relname = 'penjualan_harian';"