X
HOME HTML CSS JAVASCRIPT SQL PHP JQUERY ANGULAR BOOTSTRAP XML ASP.NET MORE...
REFERENCES | EXAMPLES | FORUM | ABOUT

Web Building - Fetching Data with SQL


Building a web site from scratch.   Part X: Fetching data with SQL.


What We Will Do

In this chapter we will:

  • Create server pages

Server Running PHP and MySQL

<?php
header("Access-Control-Allow-Origin: *");
header("Content-Type: application/json; charset=UTF-8");

$conn = new mysqli("myServer", "myUser", "myPassword", "Northwind");

$result = $conn->query("SELECT CompanyName, City, Country FROM Customers");

$outp "[";
while($rs = $result->fetch_array(MYSQLI_ASSOC)) {
    if ($outp != "[") {$outp .= ",";}
    $outp .= '{"Name":"'  . $rs["CompanyName"] . '",';
    $outp .= '"City":"'   . $rs["City"]        . '",';
    $outp .= '"Country":"'. $rs["Country"]     . '"}';
}
$outp .="[";

$conn->close();

echo($outp);
?>


Cross-Site HTTP Requests

Requests for data from a different server (than the requesting page), are called cross-site HTTP requests.

Cross-site requests are very common on the web. Many pages load css, images, or scripts from different servers.

In modern browsers, cross-site HTTP requests from scripts are restricted to same site for security reasons.

The following line, in the PHP example above, has been added to allow access to the page from a cross-site.

header("Access-Control-Allow-Origin: *");


Server Running PHP and MS Access

<?php
header("Access-Control-Allow-Origin: *");
header("Content-Type: application/json; charset=ISO-8859-1");

$conn = new COM("ADODB.Connection");
$conn->open("PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=Northwind.mdb");

$rs = $conn->execute("SELECT CompanyName, City, Country FROM Customers");

$outp = "[";
while (!$rs->EOF) {
    if ($outp != "[") {$outp .= ",";}
    $outp .= '{"Name":"'  . $rs["CompanyName"] . '",';
    $outp .= '"City":"'   . $rs["City"]        . '",';
    $outp .= '"Country":"'. $rs["Country"]     . '"}';
    $rs->MoveNext();
}
$outp .= "]";

$conn->close();
echo ($outp);
?>


Server Running ASP.NET, VB and MS Access

<%@ Import Namespace="System.IO"%>
<%@ Import Namespace="System.Data"%>
<%@ Import Namespace="System.Data.OleDb"%>
<%
Response.AppendHeader("Access-Control-Allow-Origin", "*")
Response.AppendHeader("Content-type", "application/json")
Dim conn As OleDbConnection
Dim objAdapter As OleDbDataAdapter
Dim objTable As DataTable
Dim objRow As DataRow
Dim objDataSet As New DataSet()
Dim outp
Dim c
conn = New OledbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=Northwind.mdb")
objAdapter = New OledbDataAdapter("SELECT CompanyName, City, Country FROM Customers", conn)
objAdapter.Fill(objDataSet, "myTable")
objTable=objDataSet.Tables("myTable")

outp = "["
c = chr(34)
for each x in objTable.Rows
if outp <> "[" then outp = outp & ","
outp = outp & "{" & c & "Name"    & c & ":" & c & x("CompanyName") & c & ","
outp = outp &       c & "City"    & c & ":" & c & x("City")        & c & ","
outp = outp &       c & "Country" & c & ":" & c & x("Country")     & c & "}"
next
outp = outp & "]"

conn.close
response.write(outp)
%>


Server Running ASP.NET, Razor and SQL Lite

@{
Response.AppendHeader("Access-Control-Allow-Origin", "*")
Response.AppendHeader("Content-type", "application/json")
var db = Database.Open("Northwind");
var query = db.Query("SELECT CompanyName, City, Country FROM Customers");
var outp ="["
}
@foreach(var row in query)
{
if outp <> "[" then outp = outp + ","
outp = outp + "{" + c + "Name"    + c + ":" + c + @row.CompanyName + c + ","
outp = outp +       c + "City"    + c + ":" + c + @row.City        + c + ","
outp = outp +       c + "Country" + c + ":" + c + @row.Country     + c + "}"
}
outp = outp + "]"
@outp



Your suggestion:

Close [X]

Thank You For Helping Us!

Your message has been sent to W3Schools.

Close [X]
Search w3schools.com:

WEB HOSTING

UK Reseller Hosting

WEB BUILDING

Download XML Editor FREE Website BUILDER Free HTML5 Templates

SHARE THIS PAGE

facebook