TAILIEUCHUNG - SQL Server Tacklebox- P24

SQL Server Tacklebox- P24: This book, as with almost all books, started out as an idea. I wanted to accumulate together those scripts and tools that I have built over the years so that DBAs could sort through them and perhaps adapt them for their own circumstances. | 4 Managing data growth Results j Messages â Execution plan Query 1 Query cost relative to the batch 100 Select count from book_list where bo 1 5 Stream Aggregate Index Seek NonC lustered Aggregate Book_List . Read_Date Cost 15 Cost 85 Figure Addition of covering indexes leads to an efficient index seek operation. So while indexes do indeed take space this space utilization is usually more than warranted when they are used correctly and we see the desired pay-off in query performance. The issue with indexes arises when development teams adopt a scattergun approach to indexes sometimes to the point of redundancy and harm to the database. Adding indexes arbitrarily can often do as much harm as good not only because of the space that they take up but because each index will need to be maintained which takes time and resources. TempDB No DBA who has been working with SQL Server for long will have been immune to runaway TempDB growth. If this growth is left unchecked it can eventually fill up a drive and prohibit any further activity in SQL Server that also requires the use of the TempDB database. SQL Server uses the TempDB database for a number of processes such as sorting operations creating indexes cursors table variables database mail and user defined functions to name several. In addition to internal processes users have the ability to create temporary tables and have free reign to fill these tables with as much data as they wish assuming that growth of the TempDB data file is not restricted to a specific value which by default it is not. I do not recommend restricting growth for TempDB files but I do recommend that you be aware of what will happen if TempDB does fill up. Many SQL Server processes including user processes will cease and an error message will be thrown as I will show. The TempDB database is created each time SQL Server is restarted. It is never backed up nor can it be. It is always in Simple mode and the .

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