SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd747819c79da68575d3540e83df5dd9ed5c97c14c48ceaabaeebcd5e9b18ff78' 
  AND token = '0nF54FFoV6A4CN6FHCK9JfuNUPGWBgcmiKGMztqtwrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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