You mean when you change the dimension value(In sketcher mode) at that time it regenerates full sketch. For that in sketcher tool(Inside sketcher mode) there is an icon below dimension icon, Click this icon select dimensions those you want to change and uncheck regenerate dialog box now change the value of all the dimensions as per your requirement and hit ok button. Hope it will help you. Vimlesh Patelia.
It can be done, 1) Select the dimension and then right click on it, 2) A pop up menu will appear, 3) select the Lock option from the popup menu Do the same thing for all the dimension which you want. This will ensure the dimensional lock on the geometry that you have created.