MySQL voorbeelden

On this page you can find some example SQL commands.

SQL update

Here is an example to update rows in column with specific data, as example the wordpress database where all pages are reverted to the defaul template:

UPDATE wp_postmeta
SET meta_value = 'default'
WHERE meta_key = '_wp_page_template';

UPDATE wp_postmeta

SET meta_value = 'default'

WHERE meta_key = '_wp_page_template';

SQL zoek en vervang data in een kolom

UPDATE tabel
SET kolomnaam = REPLACE(kolomnaam,'http://mijnsite.nl/webshop','http://webshop.mijnsite.nl')

1 2	UPDATE tabel SET kolomnaam = REPLACE(kolomnaam,'http://mijnsite.nl/webshop','http://webshop.mijnsite.nl')

SQL verwijder data in een kolom

DELETE FROM tabelnaam WHERE kolomnaam = 'string';

1	DELETE FROM tabelnaam WHERE kolomnaam = 'string';

PHP SQL Fetch array

Here is a PHP example to show data from a database:

<?php
// Database instellingen (MySQL)
$db_adres = 'webadres of ip';
$db_name  = 'datbasenaam';
$db_usr   = 'database gebruiker';
$db_pw    = 'database wachtwoord';

echo "- Bezig met verbinden...";

$dbcon = mysqli_connect($db_adres, $db_usr, $db_pw, $db_name);

if (mysqli_connect_errno()) { exit; }
echo "OK...<br><br>";


$query = "
SELECT product_id, minimum FROM oc_product
";


$result = mysqli_query($dbcon, $query);


if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {
      // waar minimum > 1
      if ($row["minimum"] > 1) {
        echo $row["minimum"] . "," . $row["product_id"] . "<br>";
      }
    }
} else {
    echo "0 results";
}
echo "*************************<br>";
echo "<br>";

mysqli_close($dbcon);
echo "- Einde!<br>"
?>

<?php

// Database instellingen (MySQL)

$db_adres = 'webadres of ip';

$db_name = 'datbasenaam';

$db_usr = 'database gebruiker';

$db_pw = 'database wachtwoord';

echo "- Bezig met verbinden...";

$dbcon = mysqli_connect($db_adres, $db_usr, $db_pw, $db_name);

if (mysqli_connect_errno()) { exit; }

echo "OK... ";

$query = "

SELECT product_id, minimum FROM oc_product

$result = mysqli_query($dbcon, $query);

if ($result->num_rows > 0) {

// output data of each row

while($row = $result->fetch_assoc()) {

// waar minimum > 1

if ($row["minimum"] > 1) {

echo $row["minimum"] . "," . $row["product_id"] . " ";

}

} else {

echo "0 results";

}

echo "************************* ";

echo " ";

mysqli_close($dbcon);

echo "- Einde! "

Zoeken

MySQL voorbeelden

SQL update

SQL zoek en vervang data in een kolom

SQL verwijder data in een kolom

PHP SQL Fetch array