SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e39564bd9d0cd6e42757e931e9177d7aaed79db906a68848e5f30eb0c0edaab3' 
  AND token = 'GBLMq7bkOMq6lTXjZnsH5+AeSCyJZhJD4hV55qxRw5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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