![]() This behaviour can be observed from Windows Performance Manager. So, what can you do?Įarlier in this article, I mentioned that SSAS takes time to load Databases into memory. It is possible to configure SSAS to provide feedback on what it’s doing, but that needs to be set up beforehand. I have also seen situations where SSAS has gone into an endless loop, trying to start, hitting a corrupt Database, then re-starting. I have observed a situation where engineers have re-started an SSAS Server (because that fixes everything) because it hasn’t started up in a reasonable time. If a Database fails to load then SSAS is unlikely to start. Starting SSAS is very much an “all or nothing” operation. Please feel free to email me if you can help. As mentioned in a previous post, I am learning more and more about SSAS so may well update this in the future as I learn more. SSAS does not tell you what it is doing – it has a Log file (msmdrv.log), but SSAS does not list the Databases as it loads and performs integrity checks as the SQL Server Engine does. If an individual Database fails at this point, it will be marked as “suspect”, but the SQL Server will be ready for use, together with the other Databases. It will report individually as each one is integrity checked and made available. SSAS Loading ProcessĪs part of the startup routine, SQL Server lists each of the connected Databases that it has to load. This is certainly different from how the SQL Server engine operates. It does not update the list of Databases each time another one is loaded, just once it has processed all of the Databases. The SQL Server ERRORLOG displays status information as the SQL Server starts, listing each Database as it goes through the Recovery process to ensure data integrity.įor SSAS, loading the Databases is an “all or nothing” operation. While SQL Server works in the same way, it is clearer to see exactly what is going on with the SQL Server Engine. SSAS is busy, but it won’t tell you what it’s doing and certainly won’t give you a clue on how long it’ll be before you can access data.Ĭontrast this with the regular SQL Server engine. If you try to query the SSAS Database remotely at this point, you will receive errors. SSMS becomes unresponsive, and can also block your usage of other query windows on other Servers (SSAS or SQL Server). At this point, SSAS decides it should load the Databases and perform basic consistency checks. using SSMS to connect to the SSAS Instance, right-clicking on Databases. SSAS only loads this data into memory when a user attempts to view the list of Databases – i.e. When accessing SSAS, most users want to use data held in a Database (Cube). In my opinion, this status is not entirely accurate. When starting SQL Server Analysis Services (SSAS) Tabular, the Service is quick to report that it has started (and it has). Your experiences might differ, as “classic” SSAS works differently, and you may be lucky enough to be working with relatively small Databases. Moreover, it’s not necessary to implement additional logic in different tool such as PowerShell.This article is based on my experiences with SQL Server Analysis Services Tabular, together with large SSAS Databases (Cubes) – i.e. The solution is based on metadata – therefore wrong data would be loaded into SSAS as you do processing manually aside of prepared process.Īs for the conclusion, implementing an incremental load of the data into SSAS Tabular model via “smart” SQL Stored procedure simplifies ProcessAdd command maintenance and implementation. ![]() No scripting or implementing with code acting with SSAS object model.Simple XMLA Command (You can call simply ProcessAdd against particular partition with no worries about underlying SQL command structure).(As mentioned in my last blog, it is necessary to check whether there is something to be loaded.) Solution might be clear while checking the following figure (basic steps shown below) for ProcessAdd workflow in SSIS package. ![]()
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