SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '381037c136de675bbe5bcb8496fd1ed59cc55cd17126abc42116c04201bc65f0' 
  AND token = 'GjbJpzu6lSlxxaf4Cu1ESX7Y7c9PY6tsXu90V/Ho4vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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