In this tutorial, we'll develop a secure poll and voting system using PHP and MySQL. This system will allow you to interact with your audience and display a collection of polls. You'll learn to create polls, implement a voting system, delete polls, and display the list of published polls., We’ll call query.fetchNextPage() every 2 minutes while the app is in the foreground. In other words, we will request a new page of data every odd minute in the timeline., React-Query’s useQuery hook provides several powerful options that can help you build flexible and efficient data-fetching solutions in your React applications., We make use of Placeholder in forms, to show data related to the entity. For example let's say we have an EditUser page and form. We are using Placeholder as an example while viewing this page, to show some interesting live updating status about some thing based on this user., If set, this value will be used as the placeholder data for this particular query observer while the query is still in the loading data and no initialData has been provided., What is placeholder data? Placeholder data allows a query to behave as if it already has data, similar to the initialData option, but the data is not persisted to the cache. This comes in handy for situations where you have enough partial (or fake) data to render the query successfully while the actual data is fetched in the background..