Why use indexes in SAS?
A page is the smallest I/O unit that SAS can read or write, including data set page and index file page. Index files in SAS are sorting and searching structures made by B-trees. “When an index is used to process a request,...
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SQL syntax contains a few set operators, such as UNION, EXCEPT and INTERSECT. The UNION operator concatenates the results of multiple SQL queries vertically into a single table for all matching rows, which I found particularly useful in PROC SQL while...
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Interestingly, I just found that the most searched keyword is PROC SQL, through the traffic analysis of my tiny blog. The reason possibly is: nowadays everybody knows SQL, more or less; then someone can do some parts of the SAS job by PROC SQL wit...
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How can you go home on time? Take a quick tour with these 5 tips that I was able to summarize for my students in the SAS SQL 1: Essentials class yesterday. Since they found it handy and asked if it could become a blog post, I thought I’d share
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As a Master Chief in US Navy submarines, one of my favorite sayings was “Good judgment comes from experience, and experience comes from poor judgment.” I've always had difficulty solidly learning new programming techniques in a traditional class...
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Australian merino wool sweaters, Russian watches, Swiss chocolate, Chinese silk blouses, Canadian country music, American sweatshirts, English knitting patterns, Californian pistachios, French muesli, Egyptian bracelets, Scottish kilts, the list goes o...
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In many occasions, fast access into a lookup table to find desired value is necessary. In computer science, linked list, associative array, and hash table are widely used to construct the relationship between values and keys. Hash function, like value...
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Programming is all about data structure and algorithm. For example, value comparison needs to find right data structure and iteration method. To fulfill this purpose, the first thing is to load the variable with a key-value like data structure, follow...
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