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PHP Read from a Database, part 2
PHP Read from a Database, part 2:

So, in this example you will see how we select rows that has a field which value is equal to some query value. This can also be used to retrieve a single row also depending on the query.
We do this by using the WHERE clause. Like:

WHERE id=123.

 Read from a Database, part 2

How do you Read from a Database using PHP?

As promised in the last post we are now to select a single row from the database, and display values from that row. We will make a list of our contacts in a SELECT box. Then we can choose one person, and retrieve all the information we have about that person, from our database. So, lets get started. We have to make the webpage, and by making the SELECT we will use what we learned in the previous post – reading through all content.
Put the code in a file named 'select.php' and call it in your browser.

In the code example there is some PHP put in between the HTML tags. I keep it like that, as it could be confusing if the code was separated. And the code is supposed to be in that order.

As you can see, the code handling the database, inside the HTML, is looping through the rows of your table. This is for populating the SELECT.

Then, when submitting our choice, we call the function 'doread' in the top of the page. And here we only extract one row from the table. That one row is selected by its AutoID. What is done in the SQL query;

.. SELECT * FROM contacts WHERE AutoID= . $IDnummer ..

We have, just before that, read the AutoID from the SELECT, that was done by;

$IDnummer = $_POST['contact'];

Where 'contact' is the name of the SELECT field.
And with that, we get the value of the person in the contact list that we chose, so now we can dig out that row from the table.

See the next posting for mere more exciting MySQL stuff, using PHP.

 HTML

<HTML><BODY> 
    <FORM METHOD='POST' ACTION='#'> 
    <TABLE> 
    <TR> 
    <TD>Our contacts: </TD> 
    <TD><SELECT NAME='contact'><OPTION>Make your choice
<?php 
    $con = mysqli_connect('127.0.0.1', 'root', 'Your_Passwords', 'dbname'); 

    if (mysqli_connect_errno()) { 
    echo 'Error connecting to DB'; 
    } 

    $SQL_String = mysqli_query($con, 'SELECT * FROM contacts ORDER BY AutoID ASC'); 

    while($row = mysqli_fetch_array($SQL_String))  { 
    echo '<OPTION VALUE=' . 
    $row['AutoID'] . '>' . 
    $row['Firstname'] . ' ' . 
    $row['Lastname']; 
    } 
    mysqli_close ($con); 
?>
</SELECT> 
    </TD> 
    </TR> 
    <TR> 
    <TD></TD> 
    <TD><INPUT TYPE='submit' NAME='readme' VALUE='Okay, select'> 

    </TR> 
    </TABLE> 
    </FORM> 
</BODY></HTML>

 PHP

<?php
    if (isset($_POST['readme']))  { 
    doread(); 
    } 
    function doread() { 
    $IDnummer = $_POST['contact']; 

    $con = mysqli_connect('127.0.0.1', 'root', 'Your_Password', 'dbname'); 
    if (mysqli_connect_errno()) { 
    echo 'Error connecting to DB'; 
    } 
    $SQL_String = mysqli_query(
    $con, 'SELECT * FROM contacts 
    WHERE AutoID=' . $IDnummer . '');
    
    $row = mysqli_fetch_array($SQL_String); 

    echo "You selected: " . $row['Firstname'] . " " . $row['Lastname']; 
    mysqli_close ($con); 
    } 
?>
Icons made by Freepik from www.flaticon.com Here is an example on how to SELECT a single row of field values from a database. Also see part one here
03:02:45