I have extensive experience on wordpress with PHP, MySQL, CSS and HTML. CSS and HTML are pretty standard so I will focus on the first two. I have worked on a lot of sites where I build online forms which then feed a MySQL database. Then – on pages we can place items from the database. For example, lets say it is an Ecommerce site and so we are doing products. Each product has a unique product id; and that is in the database. So all we need do is send the product id to a page (with query string or other means) and then the PHP code on the page can look up everything in the database about that product (including images) and place everything on the page where it needs to be. Also styled exactly how we want it. Here are some sites I have worked on where this has been done extensively:
1. Member Site: Our demonstration of a member site; this involved users filling out forms including pictures for item listings (like ebay), personal info (member profile) and finally on the member updates page they can post updates and other members can comment on them. All of this was done through PHP and MySQL.
2. Gcommerce Template: this was different than the member site above in that the forms for adding products were all in the wp-admin so that only site owners can control the products. Another item on this site was the use of multiple categories and sub-categories for the products. We also setup a cool control panel in the wp-admin where site owners could view, edit, delete products. Also – we custom built a “review” system for the products that visitors can review the products including a star rating and also (yes or no) to the question “Would you recommend this to a friend?”
3. Event Calendar: no pictures handled through the database on this one. A function was built so that site owner could enter an event with event type, start time, day, month, year and price. The event was placed on a calendar on the correct day and linked to a product in the shopping cart at the correct price. There was a color code for the type of event, and events were placed in proper order by time if more than one was on the same day.
4. Calendar & Time Slots: This involved many forms visitors would fill out about their vehicle – and then they arrive at a calendar where they pick their day. This would allow them to choose a time slot for their appointment. Once they placed their order, that time slot on that day was marked “unavailable” on the calendar.
5. Woocommerce Database Automation: This site was a “drop-ship” site with 20,000 products. All products were provided by two vendors. They updated all product details on .csv and .xml files daily. Functions were built to take all info from these data files and update all products on the site.