SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf23b866be14455abb9ac2956661f5c41717092da7a08ca960274b391f5ce324' 
  AND token = '17NdS1JL1AhvUjz6PCGUpBI2ronTS35urfoO/ixOsTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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