SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '228bb9afd8cb3ed4d4d185113050ce1f45529639103efc896610f3790f17e9c0' 
  AND token = 'R8POj/dW5IISCLg7QXQAPhDDKgbXk8bEyaS7KaU5kHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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