SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acbca30739ab3f1e1371e2f61d0f93e3dac767cce54b95b228c09c4a5ea7dd56' 
  AND token = 'UwDgsgxYjKlNGZSjJ8aR1K7dmUnwIu7nxDv8F5hWv+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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