Tag Archives: oracle
Most people use storage snapshots with Oracle DB these days. Its easy to restore DB to discrete point of time, i.e. to snapshots time. Here is a method of rolling forward the DB to any needed point of time using … Continue reading
Recently got involved in couple conversations regarding common “RULE OF THUMB” about backing up control file, and double backup of control file backup etc.. I guess its good thing to do, its does not take much space anyway, but if … Continue reading
Its Unix 101 statement, but I have heard it wrong so many time, so decided to put a blog for it. So: If in OLTP environment, per ‘top’ %wa (IOWAIT) is major contributor for CPU busy, adding CPU would not … Continue reading
Term of “TOP-N” intuitively makes thinking what they query should run faster than just ORDERED query, as only N elements needed from it. But, as well known, not always.. This blog describes method how using proper index would optimize TOP-N … Continue reading
Index Clustering factor. One way how to avoid negative performance impact on joins which involves bad clustered indexes.
High Index Clustering factor is popular problem in SQL world. The most known solution for it – rebuild table ordering by columns what are in the index. But in real world, with table size growing exponentially its not always practical … Continue reading