Delete wordpress post revisions

To delete and remove all existing post revisions entries and rows from WordPress database posts table, login to phpMyAdmin, select the appropriate WordPress database and then issue the following command :

DELETE FROM wp_posts WHERE post_type = ‘revision’;

To turn off and disable automatic post revisions, simply add the following line of code to wp-config.php file located in the root or home directory of WordPress blog:

define(’WP_POST_REVISIONS’, false);

Popup window with parameters

If a new window is created by an user action, it will not be blocked by the browser’s popup blocker.

The dimensions (width & height) of the popup window are required, the other parameters are optional:

  • left & top :  the distance from the top and left side of the screen
  • toolbar :  if the popup should have a set of navigation buttons across the top
  • location :  if the popup should have a location bar where the URL is displayed
  • directories :  if the popup should have a row across the top with buttons to popular web sites
  • status : if the popup should have a status bar across the bottom
  • menubar : if the popup should have a menu
  • scrollbars : if the popup should have scroll bars
  • resizable : if users can resize the popup
  • dependent : if the popup should close when its opener window closes
  • full screen : how to open a full screen popup

The popup script has the following format:

window.open(href, windowname,

width=400,height=200,scrollbars=yes’);

An example is given below:

[HTML1]

Dream Bank

Last update : August 9, 2013

The Psychology Department of the University of California, Santa Cruz, offers access to their Dream Bank, a collection of over 20.000 dream reports in English and 6.000 dream reports in German, coming from a variety of different sources and research studies, from people ages 7 to 74.

The reports can be analyzed using a search engine and statistical programs built into the Dream Bank website. Several of the people who contributed dreams to the Dream Bank wrote prefaces to their journals which are also available. A summary of the collection available for search is presented in the grid.

D. William Domhoff wrote a contribution “Fast Content Analysis Using the Internet” in 2004 based on the search engine. More recent findings have been published in Consciousness and Cognition (17, 1238-1247) in 2008 in the contribution “Studying Dream Content Using the Archive and Search Engine on Dream Bank.net“.

3D data sculptures

Today 3D sculptures can be created with 3D plotters and standard 3D modelling software. These tools allow digital artists to transform large data sets into a physical form.

~IDENTITÄT – The »Gestalt« of dig­ital identity

A recent project in this area has been done by Jonas Loh and Steffen Fiedler as a bachelor thesis at the Studiengang Interfacedesign of the University of Applied Sciences Potsdam, Germany, with the help of the 3D Lab of the TU-Berlin. The project called ~IDENTITÄT – The »Gestalt« of dig­ital identity eval­uates how dig­ital identity is generated to determine pa­ram­e­ters on which a compa­ra­ble anal­yses of the dig­ital identity is pos­sible. The concept, the process and the results are published at the website www.digital-identities.com. Photos of the whole project are available at the flickr collection. The project was tutored by Prof. Boris Müller.

Other 3D sculpture projects are :

Web Design : em versus pixel

Last update : June 24, 2014

Because of the wide range of settings and equipment that people might be using to access the web, there is no “best font size”. Font sizes should be specified using relative units like percentage or em since these will allow the user to adjust font sizes up or down to suit their own requirements.

With CSS you can specify font size as a percentage of the font size of a parent element. For example, headings are inside the body of the page. If you don’t set a size for the text in the body, the text of the body will be the size that the reader has chosen as their default size. An ’em’ is equal to the computed value of the ‘font-size’ property of the element on which it is based. The exception is when an ’em’ occurs in the value of the ‘font-size’ property itself, in which case it refers to the font size of the parent element. It may be used for vertical or horizontal measurement.

A default font size of 16 pixels is used for the body if the browsers are configured as follows :

  • Internet Explorer, choose View>Text Size>Medium
  • Opera, choose View>Zoom>100%
  • Firefox, choose View>Text Size>Normal

Some web designers recommend to set the font size in the body to 10 pixels (63%) to allow easier calculations of the em-values (in this case 1.4 em gives a font size of 14 pixels). In the case of embedding elements, this gives no real advantage for the calculations.

em versus pixel

The following table shows the relations between pixels and em’s for different font-sizes, based on a default font size of 16 pixels = 1.0 em.

font-size pixels em
xx-small 9 0,56
x-small 10 0,63
small 13 0,81
medium 16 1,0
large 18 1,13
x-large 24 1,5
xx-large 32 2,0

Lorem Ipsum

Last update : August 19, 2016

Lorem Ipsum

Lorem Ipsum

Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry’s standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout. The point of using Lorem Ipsum is that it has a more-or-less normal distribution of letters. More informations about Lorem Ipsum and an online generator are available at the lipsum.com website.

A more recent artisanal filler text generator is Hipster Ipsum. A hipster is a person who follows the latest trends and fashions, especially those regarded as being outside the cultural mainstream. Ian Van Ness, senior hardware tools developer at Apple, created HipsterJesus, an API to create Hipster Ipsum texts related to the bible. Hipster Jesus is an Internet Meme referring to a series of images of a glasses wearing version of Jesus Christ.

PHP foreach loop

A foreach loop can be used in PHP  with an array instead of a counter. If an array contains 5 pieces of data, then the foreach loop would execute 5 times.

A foreach loop is phrased like this: foreach (array as value) { what to do; }

Here is an example of a foreach loop:

<?php
$a = array(1, 2, 3, 4, 5);
foreach ($a as $b)
{
echo $b;
echo (‘<br/>’);
}
?>

Authentification

Authentication is a process for identifying and verifying who is sending a request. The following list shows a simplified version of an authentication process :

  • The sender obtains the necessary credential.
  • The sender sends a request with the credential to the recipient.
  • The recipient uses the credential to verify the sender truly sent the request.
  • If yes, the recipient processes the request. If no, the recipient rejects the request and responds accordingly.

Amazon® Product Advertising API with signed requests

By August 15, 2009, all calls to the Amazon® Product Advertising API must be signed to authenticate the request. Ulrich Mierendorff developped a simple function in PHP that lets you make authenticated requests with only a few lines of code. He is also the author of “Antialiased filled Arcs/Ellipses” for PHP and of the rounded css boxes.

Other PHP example for Amazon signed requests have been posted by Mark on his blog “Every Good Path” and by Horacix on his blog “Inside Things“.

Amazon’s guidelines for signing requests are available on the AWS website.

The following error messages are sent:

  • the timestamp is old : Request has expired