Dynamic Data Source based on parameter

[shaunwilks]

Hello all,

Hopefully this is easier to explain that Im finding it is to do.

I have done work with parameters that place the SQL Server and Database names into the Source in the Advanced Editor.

Its working well and I feel comfortable in what its doing.

However I am scratching my head over syntax errors Im getting trying to do the following.

The data source for the Query may come form TableA or TableB.

A list of fields will be included that is slightly different in both tables so not as easy as passing the parameters in the Table section of the Select * From <<Table>> area.

I would like to have a parameter that is effectively a Yes/No question.

If the answer is a Yes, then I would like the "Source =" line in advanced editor to be the full source line for TableA

If the answer is a No, then I would like the "Source =" line in advanced editor to be the full source line for TableB

In concept its simply

Source = If parameter = yes then Sql.Database(.............TableA else Sql.Database(.............TableB

Im just really struggling with the syntax and the old Token Comma expect is often arising.

Thanks in advance for time taken to read or reply

[Tony_XXX]

thanks for sharing this great idea!!! 😛

[Anonymous]

@shaunwilks,

I am not very clear about your logic, could you please post a screenshot about the code in your Advanced Editor? How do you create parameter in Query Editor?

In your scenario, why not create another table name parameter?


Regards,
Lydia

[shaunwilks]

Sorry if I was not clear enough but you are on the right track in response.

The data source is not as simple as the Table name, Sql server name or database name.

It could be excel or SQL, it could be a different sheet name in different excel or different table in a different SQL database.

I wanted to present the 3 or 4 options in a plain english list of options in the "Parameter" and then handle the data source inside the M code.

So for simplicity sake the parameter would read Option 1, Option 2, Option 3,Option 4....

I wanted the M code to read something like

If Parameter = Option1 Then Source = Excel.Workbook(File.Contents("C:\Data.xlsx"), null, true) else

If Parameter = Option2 Then Source = Excel.Workbook(File.Contents("F:\Database.xlsx"), null, true) else

If Parameter = Option3 Then Source = Sql.Database(SQLServer, AdventureWorks, [Query="SELECT * FROM Data", CreateNavigationProperties=false]) else

Sql.Database(SQLServer99, AdventureWorks, [Query="SELECT * FROM DataView", CreateNavigationProperties=false])

Continually having syntax issues trying to achieve it and was hoping a sample "If" statement could be provided that changes the data source property in the Advanced Query Editor

[Anonymous · Accepted solution]

@shaunwilks,

Here is an example for you.

let

#"Table 1" = (para as text) =>
if para = "test1"
then

let
    Source = Sql.Database("servername", "test",[Query="select * from Main"])
   in
    Source

else 

let
    Source = Excel.Workbook(File.Contents("path\Book1.xlsx"), null, true),
    #"Security public - Copy_Sheet" = Source{[Item="Security public - Copy",Kind="Sheet"]}[Data]
    in
    #"Security public - Copy_Sheet"

in #"Table 1"

Regards,
Lydia

[jnogle]

This is an amazing solution!

I am building a template for users that may decide to use SQL or Excel as their data source and this is much more elegant than maintaining 2 versions of the same file (one for each data source).

I took this solution one step further by referencing an already defined parameter to determine which data source to use. So, when the user first opens the Power BI file as a template, they are presented with a "Data Source" parameter option where they can select either "SQL" or "Excel" from the list. The table is then populated with the appropriate source based on this choice.

I'm still working out the best solution for handling connection parameters (SQL requires Server, Database and Table parameters, but Excel only requires a path parameter) but there are multiple solutions to explore there.

Here's a code example:

if #"Data Source Type" = "SQL"
then

let
    Source = Sql.Database(#"SQL Server Name", #"SQL Database Name", [Query="SELECT * FROM [dbo].[view_" & #"Table Name" & "]"]),
    #"Extracted Date" = Table.TransformColumns(Source,{{"Date", DateTime.Date, type date}})
in
    #"Extracted Date"

else

let
    Source = Excel.Workbook(File.Contents(ExcelDataFile), null, true),
    FactTable_Sheet = Source{[Item="FactTable",Kind="Sheet"]}[Data],
    #"Promoted Headers" = Table.PromoteHeaders(FactTable_Sheet, [PromoteAllScalars=true]),
    #"Changed Type" = Table.TransformColumnTypes(#"Promoted Headers",{{"Value", Int64.Type}, {"StageIndex", Int64.Type}, {"Date", type date}, {"Version", Int64.Type}, {"OsBuildRelease", type text}, {"DeviceFamily", type text}, {"FlightRing", type text}})
in
    #"Changed Type"

[soni27]

Thanks for Sharing Very Usefull Idea

[shaunwilks]

Thanks so much Lydia.

I was tackling it a little different to that but your way is nice and clean.