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  Sometimes we need to move the database from one instance to another instance. But we don’t dare to erase our old database right away. …

  We find the number of records in a data set with the Count function. For example, we can find the number of records in …

  Rman creates a control file snapshot file or a consistent control file image in the control file backups. While a rman process taking a …

What is DeadLock? Although it is like a movie star, it causes serious problems in applications. If we want to briefly summarize DeadLock, two or …

Application developers sometimes receive a deadlock error and cannot see which queries are deadlocked. That’s why they demand this information from you. We can capture …

  We can see the locks on Library cache objects in V$ACCESS (GV$ACCESS on RAC systems). The dependency on objects is managed by library locks. …

  You may receive this error when you want to import data from a file such as Excel to the sql server. You must install …

  We can create subtotal and grandtotal rows for the grouped data with WITH ROLLUP, WITH CUBE and GROUPING SETS operators. You can find details …

We use the WITH ROLLUP and WITH CUBE operators with the GROUP BY statement. So before you read this article, I suggest you read the …

SQL Server supports grouping of data with GROUP BY since older versions, and also offers WITH ROLLUP and WITH CUBE operators for grand-total and sub-totals. …