SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fa625765daa3fd99b5798206e9219b22295e9380d58512e3644177502e2348c' 
  AND token = 'daqQcLVDir3fx1xr9J4GrWkMGEzS84h3VhZqvqmtYjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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