Well this one will be in English since I will use an English quote. I was sad to discover, that the php function that I had actually learned to love, which took me quite some time in the first place, is not so nice after all :o( At least not when speaking of performance. Colleagues of mine had for a long time tried to convince me to use sprintf and printf function because they are secure; you cannot use injections and you furthermore make sure you supply the right types. In addition  (when you get used to it I might add) it is also a rather easy format to read. So now look what I read on some papers that I actually printed out long time ago. Its written by Ilia Alshanetsky and its about tricks for optimization in Php. "Using printf() is slow for multitude of reasons and I would strongly discourage it's usage unless you absolutely need to use the functionality this function offers. Unlike print and echo printf() is a function with associated function execution overhead. More over prinf() is designed to support various formatting schemes that for the most part are not needed in a language that is typeless and will automatically do the necessary type conversions. To handle formatting printf() needs to scan the specified string for special formatting code that are to be replaced with variables. As you can probably imagine that is quite slow and rather inefficient." Nevertheless, I will still use printf() and sprintf() when I think they are needed but I think I will start using them with more consideration. I have been quite satisfied using the functions when writing my mysql queries, since in these situations it is more necessary than anywhere else, to make sure the code is secure. I will thus continue using them in these situations.