how to find exactly data between selected diagonal area in mysql query

Question

These are my coordinates of Selected diagonal points, will be more when select

Answer 1

To eliminate the points within your bounding box query but not within polygon you require to use Point in Polygon algorithm.

The easiest way to do this is to have the coordinates in arrays. These can be used to find max and min coordinates for the query and for parameters for pointInPolygon() function.

function pointInPolygon(polySides,polyX,polyY,x,y) {
 var j = polySides-1 ;
  oddNodes = 0;
  for (i=0; i<polySides; i++) {
    if (polyY[i]<y && polyY[j]>=y  ||  polyY[j]<y && polyY[i]>=y) {
        if (polyX[i]+(y-polyY[i])/(polyY[j]-polyY[i])*(polyX[j]-polyX[i])<x)  {
            oddNodes=!oddNodes; 
        }
    }
   j=i; }

  return oddNodes;
}

In your Map code using jQuery getJSON()

var polySides = 4;//number of points in polygon
//horizontal Latitude coordinates of polygon  
var polyLat = new Array();
polyLat[0] = 51.5;
polyLat[1] = 51.5;
polyLat[2] = 52.5;
polyLat[3] = 53;
polyLat[4] = 51.5;//First point repeated to close polygon
//vertical Longitude coordinates of polygon 
var polyLng =  new Array();
polyLng[0] = 0.5;
polyLng[1] = -1.9;
polyLng[2] = -1;
polyLng[3] = 0.6;
polyLng[4] = 0.5;
//Coordinates for bounding box
var maxLat = Math.max.apply(null,polyLat);
var minLat = Math.min.apply(null,polyLat);
var maxLng = Math.max.apply(null,polyLng);
var minLng = Math.min.apply(null,polyLng);

//Using jQuery
var url = "yourFile .php";
 url +="?maxLat="+maxLat +"&minLat="+minLat +"&maxLng="+maxLng +"&minLng="+minLng;
 $.getJSON(url,function(data) {
    $.each(data.marker,function(i,dat){
        if (pointInPolygon(polySides,polyLat,polyLng,dat.lat,dat.lng)){
            var latlng = new google.maps.LatLng(dat.lat,dat.lng); 
            addMarker(latlng,dat.name);
            bounds.extend(latlng);
        }
    });
    map.fitBounds(bounds);
});

Map obtained using Bounding Box and Point in Polygon.