SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34723b5a2f04cbe7df85f74f51ab438c8d49163580a188a9cffd3ababfaf7dd7' 
  AND token = 'rjOmsuGq3pLIoliU1XdzLR3u22VFUwAmdffcyZQc9LY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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