SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '802ad0db4c7aed18de94bc06d0d25fd7037fe6277c26fb0caaecfa74fe31b935' 
  AND token = 'bDWR/BroZPj2FCcA2OXav3riFhttcpuKogPiyKuwK4c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}