如何在后台连续运行ajax请求?

I want to show data as soon as new data is entered, but I do not want that user always refreshes the page to see new data.

You can use a php script to call ajax url like

$(function(){
  getAjaxRequest();
});

function getAjaxRequest(){
  $.ajax({
    url:"someurl.php",
    data:{data:"data"},
    success:function(result){
       //result retrieval queries
       //and
       setTimeout(getAjaxRequest,1000); //call the same function every 1s.
    },
    error:function(err){
       //error handler
    } 
  });
}

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