SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12ddced27fff8ba61049a4c5f60c7f6fd0dc6fe779498212b981ba8056943986' 
  AND token = 'wW72Eyf+y1k/Zh/xCQ0A1XnrB1VDulzJlgnGV9ab0mc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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