Forum Discussion
Restrict rows retrieved by query?
- 10 years ago
The single-qoutes is needed as part of my SQL query to filter a string column in the SQL database
The 1st double-qoute stop the "free text query" and allows to insert a parameter
Ampersand is needed to merge the parameter with the SQL code around paramater
The 2nd double-qoute continue the "free text query"
I hope this explains the code.
Now back to your problem... 19 foreign keys "scary face". I assume that you users will need to be able to filter several parameters at once? This will force you to type SQL code from now until you retire. As I see it you will have to create 19*18*17*16*15*14*13*12*11*10*9*8*7*6*5*4*3*2 combinations of your code + create 19 parameters lists with a complete set of values for your user - and this will only give them the option to select a single value per parameter. I don't think this is the right path for you. You will need to many different variations of your code because consider that your user only select a parameter in a few of your lists, then the rest will be blank but if you query your SQL with WHERE a.Country = '' then you will only get the customer with no country value (blank), but what you really want is not to filter the country column in your SQL table, so you will somehow have to handle all the combinations of posible where clauses you need.
With single value per parameter I mean they will not be able to select both US and UK customers but only one of them - unless you make you parameters free text values. Then you will be able to chance the SQL to use IN instead of =, but your users will only get the wanted result if they learn to write the right text - using my example from before this would be 'US', 'UK' and your where clause should be "WHERE a.Country IN (" & CountryParameter & ")"
I'm sorry, I don't understand your response. What approach is "better than 'here is all the data, ask yourself'"?
What I am looking for is the capability to create custom queries in Power BI as the basis for reports and visualizations - not limiting it to generic queries or pre-defined queries built by a guru, but letting end users build their own queries, reports and visualizations without having to be an expert in SQL, DAX, M or some other specialized language or feature set in order to limit the data they look at. SQL Server should do the work of retrieving the appropriate rows (which it can do quickly and efficiently), the tool should not require the user to bring in all of the data and create complex mechanisms to filter it down to the data they want. Can you imagine refreshing a query on a regular basis, if it retrieves all rows and then filters them? Ugh!
But it seems that's just not possible with this tool. Is that correct? Too bad, the capabilities of Power BI are great for end-user analysts to define and publish useful management and staff visualizations, but the learning curve is too steep (or the tool is not appropriate) if there's no simple way to do such things.
Am I missing something? I'm new to the product, so that's very possible - and the purpose of this question. I'd like to use Power BI if it has the needed capabilities.
Thanks for your response and help.
SamTrexler Is there some reason that you haven't gone down the modeling route? Using SSAS Tabular for instance? Everything you describe as it relates to an end user filtering/slicing and dicing without the need for complex queries is the purpose of developing a BI layer to your relational data. The end result is a model that contains the pertenant business information, and gives the end users the ability to search anything they want in the model.
- SamTrexler10 years agoHelper IV
Anonymous, that's where we're headed. We're looking at using SSAS Tabular modeling for business analytics. But at this stage of the project, we have flattened operational data that we intend to load into SSAS, and I was wondering if we could use that data for operational analysis as well - retrieving detail rows for analysis instead of the lowest level of aggregation.
I have prototyped this in Excel using a Microsoft Query data connection and applying criteria to the query that are linked to cells in the spreadsheet. This gives the user the ability to change the value of the parameters in the spreadsheet and get the corresponding rows. It's also not too hard for someone experienced in Excel to add criteria to the query, without knowing SQL. (There are some gotchas there, which we'll need to train on.)
When I saw Power BI, I liked the power of reports, visualizations and dashboards very much. And I wondered if it could do the same thing, with greater presentation capabilities. But it appears the answer is no, so we may have to remain "old school" with Excel and Microsoft Query, unless someone has a solution or recommendation?
Thanks.
- Anonymous10 years agoNot applicable
SamTrexler Take a look at Parameters, they were just added to the Desktop in the April release. They may provide a way to filter the information, but I haven't played with them yet enough tell you how they work and/or if they'll work for your use case.
- SamTrexler10 years agoHelper IV
Eno1978, Thanks for your responses.
I have looked at query parameters, but can't find a way to have them affect the SQL statement sent to SQL Server, without resorting to coding on the Advnaced Editor. And this needs to be an end-user capability, so that's out for my immediate purposes.
Any suggestions?
- v-qiuyu-msft10 years agoCommunity Support
Hi SamTrexler,
I agree with Anonymous that the Query Parameter feature is the thing you are looking for. We can create one or more query parameters, then add filter conditions to limit data based on parameter values. When the user runs the report, the Enter Parameters window will popup and user can check his prefer values to filter rows. Please take a look at links below:
Deep Dive into Query Parameters and Power BI Templates
If you have any quetsion, please feel free to ask.
Best Regards,
Qiuyun Yu- SamTrexler10 years agoHelper IV
Qiuyun_Yu,
Thanks for your feedback. The first of the links you gave was informative and I hadn't seen it before.
The problem I'm having is trying to relate the query parameters to the SQL Server select statement. As the link shows, it is possible to change the values used for a data source. And there are some good blogs that show how to change the SQL Server instance that the query connects to, for example. But I cannot find a simple way to modify the SQL query so that it incorporates the query parameters, without learning the new language and creating very specific code in the Advanced Editor to use it.
I'm new to Power BI, so please correct me if I'm wrong, but the problem I see with using filter conditions is that SQL Server will still return all of the universe of rows it contains, and the filter will be applied when it is displayed or used in a visualization or report. I do not want SQL Server to return 123 million rows so that the user can filter down to the one thousand or so rows he/she is interested in. Instead, the user should be able to enter values for the parameters, which are then sent to SQL Server as part of the query, and it returns just the one thousand rows of interest.
Is this possible? I haven't found a way to do it, but I sure would like to - without advanced coding, something our users can set up and do. Each user will have specific columns of data they are interested in seeing from the operational data store, and specific criteria to use to select the rows they are interested in. And the number of such requests is huge - far more than our staff can develop for each user. Essentially, we would like Power BI to be an end-user ad hoc tool for operational data as well as for aggregated data from sources like SSAS. And I'm not seeing a way to do it.
Thanks for yoru help.