MySql Select命令返回空值

Question

I have a simple php code which enters value into MySql database and then retrieves it and displays it. However when retrieving it always return null and Empty Set is echoed everytime. Can someone please help.

I am using WAMP Server.

Database name is trial and name of table is People. It has 2 attributes: name and email id

Following is my code:

$con=mysqli_connect("localhost","root","");

if (mysqli_connect_errno())

       echo "Failed to connect to MySQL: " . mysqli_connect_error();

mysqli_query($con,"INSERT INTO People VALUES ('xyz', 'abc@zzz.com')");

echo "Insertion Success";

$result = mysqli_query($con,"SELECT * FROM People");

if($result == null)

    echo "Empty Set";

else

   while($row = mysqli_fetch_array($result)) 
   {
       echo $row['name'] . " " . $row['emailid'];
       echo "<br>";
   }

   mysqli_close($con);
?>

Answer 1

You should select a database after using mysqli_connect but before any queries are done:

$con=mysqli_connect("localhost","root","");

if (mysqli_connect_errno())

       echo "Failed to connect to MySQL: " . mysqli_connect_error();

mysqli_select_db($con, "databasename");

//query processing here..

Answer 2

You should check if record is inserted change your code to

if( mysqli_query($con,"INSERT INTO People VALUES ('xyz', 'abc@zzz.com')") === FALSE){
    echo mysqli_error();
}

Answer 3

first always check if you query executed write by executing it inside if():

if(!mysqli_query("your query"))
   {
     mysqli_error();
   }

second i think your query is not executing because you cant name you table with a capital letter so it should be "people" not "People"