This is just a reblog of On SQL*Plus Defines directed by SQL*Plus default values for script parameters, so credits go elsewhere. However, it’s such fun to recognize this guy employing the schortcomings of a 1st/2nd generation language such as sqlplus to actually overcome another distressing deficiency which is the lack of optional, at least fixed left-to-right positional command line parameters.
So what Vlad just does is to overwrite the binding value of an unprotected intrinsic variable for command line input transfer. Namely, he knows that command line input bindings like &1 and &2 and so forth will always exist in the runtime realm of the processor and purposeful overwrites one or the other positional binding by declaring a column blabla new_value 1,2,... slots of just the same name. That’s cool stuff, really, since it provides for a default value setting on a missing input. Something, sqlplus does not deliver, according to the manuals.
Real fun, have it
Every wiki landing page usually features a kind of overview layout to provide links to the most interesting topics or articles. This might constitute a classic table of contents, quite lengthy at times, a tag cloud of the hottest keywords (and relations, maybe), for iterative exploration, or, if you like, a dashboard of context grouped / block visualized widgets of important articles. Whatever you prefer, me, I almost always take on the dashboard approach, because it provides a great productivity in information to space ratio. Furthermore, dashboards also greatly serve the figurative memory in that one can plainly remember some article link resides in a widget up in the upper right corner of the page or yet within another widget with an outstanding background color.
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