源图表上的Google图表脚本返回错误＃0轴的数据列不能是字符串

Question

以下使用Google图表的脚本会返回错误

轴＃0的数据列不能是字符串

基本上每天都会进行预订，并且当预订被视为具有不同的属性时，它们是有效的。它应该计算booking1_date并返回该日期的数字并显示但不显示。

<script type="text/javascript">
 google.load("visualization", "1", {packages:["corechart"]});
 google.setOnLoadCallback(drawChart);
 function drawChart() {
 var data = google.visualization.arrayToDataTable([

 ['booking1_date', 'bookings'],
 <?php 
 $query = "SELECT count(status) As count, booking1_date FROM crm  where status = 'Active' GROUP BY booking1_date ORDER BY 
     CASE
          WHEN booking1_date = 'Sunday' THEN 1
          WHEN booking1_date = 'Monday' THEN 2
          WHEN booking1_date = 'Tuesday' THEN 3
          WHEN booking1_date = 'Wednesday' THEN 4
          WHEN booking1_date = 'Thursday' THEN 5
          WHEN booking1_date = 'Friday' THEN 6
          WHEN booking1_date = 'Saturday' THEN 7
     END ASC";

 $exec = mysqli_query($con,$query);
 while($row = mysqli_fetch_array($exec)){

 echo "['".$row['booking1_date']."',".$row['count']."],";

 }
 ?>
 ]);

 var options = {
   title: 'Bookings this week'
 };

 var chart = new google.visualization.ColumnChart(document.getElementById("columnchart"));
   chart.draw(data, options);
 }

 </script>