SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f232a421f9e5e0191553402aa7759acb860c10cdb6b6a2b3484b73545a99235' 
  AND token = 'O/hKxo6SXOZFbJ03JGRsBjSO/mQhLwqxBJpa2AAGHMQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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