Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75eabf7136549f99032603af16eec268ed97df1dcccd77f687d0ea8cc3ca038c' 
  AND token = '3I4ZxFKpJb2zCFlWX1PD7hZyBlpWgiSRWOYehB+Nn0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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