SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed164ab954062e437dd28d93f5a2aadcf8dc311947ab3d3f230f28d54142214e' 
  AND token = '4iGXQ7wJ95qzYvgZlEKyZVqAE7LqSaUnOcnAh2AUBbg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}