Experience is not something to learn from book reading. To be an experienced must have to work, work till the depth is found clear and vivid. Books are always good to learn the knowledge but the implementation is far beyond the reading and learning a book. A lesson from books might be forgotten but not the experience especially in some exceptional situations.
This is a very small incident I am sharing but gave me a lot of preventive measurements and precautions before doing anything.I remember during my graduate course of databases was offered as a compulsory subject. Though I do not like the subject of databases yes I never hated or reluctant to learn either. The subject went fine teacher taught wholeheartedly and class learnt including me also the subject of database became a prerequisite for many courses later offered during graduate. When the course of web development offered I chose a Dynamic web project of online Utility billing system. It was dynamic because it was a database driven web development project.
I started working with my two other project mates. Since the project is divided into two parts of web pages design and database design and then combine both of them to come with a complete operational solution. We designed web pages and core databases of the project of the online billing system. Let me explain for the one who does not have much idea of the database a web development. Working on this kind of project is something like icing bag used with nozzles of different size and designs. Once you have filled an icing bag with icing of any colour and flavour you can make several designs by changing nozzle or variations of techniques for icing. Something is similar to a database. Once you have accurately filled data in the database with all of the necessary requirements, you can apply different techniques of query language to see data in different ways.
When we were done with our core designs of database and web pages we started to retrieve data from the database to web pages. This is almost the last phase of the project to connect database with web pages and web Forms. All of us member entered computer lab early in the morning around 8:00 AM and started our work to fetch data on web pages from the database. We used one technique but data was not appearing on the page then the second and so on changed the alternate methods but all was in vain. We were all worried and could not figure out our mistake, we managed to get help from our seniors and other class fellows but no one was able to work out. It was around 3:00 PM after trying hard each and every technique of database connectivity, I switched to work on to prepare a printable document of the project. While I was taking the snapshots of the database I came to know that there was no record fed into the database and no record was displaying on web pages because of it. You can also assume icing bag was not full of icing and we were trying to create different designs by changing the nozzles and different techniques.
It was because one of the members working on delete queries accidently removed all of the records from the database and we did not notice. We reworked on it submitted the project got good grades in the course. But from that day I became cautious and my other friends too at least for the rest of the graduation courses. From that day onward before doing anything I started taking all kind of precautionary measurements. Though it was only a course project but gave us to change our attitude lesson also there were so many books we consulted about web development and database but we got a useful lesson by working on and by experience.