Preview.Error: The current preview value is too complex to display when using WebAPI

[Vanchy_Liao]

Hi,

    I am trying to use Web API to deliver Data to end user.

    My Developing environment is:

    1. windows server 2019: to develop Power BI

    2. windows server 2019: to develop Web API 2 and hosting IIS

    3. Using Power BI Desktop RS

    I create a DB view and use a Web API returning the data in JSON format

    The view contains 20 columns and returns about 32,000 rows.

    When I put the url on Edge and IE, it works differently. (The JSON file is 14.42 MB)

    1. Edge takes approximately 1.3 minutes.

    2. IE takes in 3 sceonds.

    And when I use "Web" connector in Power BI, it will take a long long time and show the error "Preview.Error: The current preview value is too complex to display".

    Is there any server settings I can change?

    Or I just have to change  my view into many small parts?

    Or it just Power BI issue?

[Vanchy_Liao · Accepted solution]

I overcome this issue myself.

First, the difference between Edge and IE might caused by the browser security settings I guess.

Second, the bottleneck is not on the Web Connector and it's on the JSON Connector.

Because I save the JSON as file and import it into Power BI using JSON Connector, then it shows me the same message:

"Preview.Error: The current preview value is too complex to display"

Finally I edit my Web API making it return in XML format.

My report just come alive again!!!!

I sacrifice the file size and choose XML Connector.

[Adel]

Hey, it might be a Power bi issue, if you don't mind me asking this data you are trying to pull is from which platform?