Getting started with power BI

Johnny C

Well-known Member
Nov 7, 2006
Right. I started Power BI this morning for the very first time. I've had no training (the power BI guy here is always too busy).

I've very familiar with Excel and Access, have worked as a SQL Server developer so I know what I want to do, just not how. So, baby steps for my first table.

I've imported a table with account codes and various mappings for higher level cost types. I've brought in another table with team codes and higher level mappings. Finally I've brought in a table with a financial forecast with account codes and team codes and months and values. I've defined relationships where I can but Power BI seems to have interesting views of what constitutes a many to many relationship.

What i want to do in the first instance is create a summary of the forecast by using the higher level mappings for account and team codes and summarising all months for each combination of the account/team. Seems simple enough, a 5 minute job in Access.

I started off creating a new table with a distinct higher level cost type, then tried to add a column with a high level team type, but it gets upset that there are multiple values in the team type. I presumed it would create every team type for every cost type.

A single value for column 'Team_Name' in table 'tblTeam' cannot be determined. This can happen when a measure formula refers to a column that contains many values without specifying an aggregation such as min, max, count, or sum to get a single result.

So, is a new table a bum steer, do I need to create a query to generate the table?

Also, to avoid asking oads of stupid questions, can anyone suggest a good tutorial or training resource for Power BI?

I'm not using Power BI to generate a stack of visuals, I'm trying to use it to create a cost forecast of the type
Base cost
Next years cost = Base cost + inflation (calculated) + known additional costs (in a table)
Year after's cost = Next years cost +inflation (calculated) + known additional costs (in a table)
and so on

I know Power BI probably isn't the best place to do it, but I'm being pressured to shift the forecast out of Excel and my options are Access or power BI. It's too complex for Access for various reasons, Access could do it but due to the volume of data sources and queries would be unmanageable. So I'm seeing what the options are with Power BI. is this a reasonable ask?

Last edited:

Excel Facts

Add Bullets to Range
Select range. Press Ctrl+1. On Number tab, choose Custom. Type Alt+7 then space then @ sign (using 7 on numeric keypad)


Active Member
Apr 30, 2014
Office Version
  1. 365
  1. Windows
The error you show is pretty common for those of us just learning the PowerX toolset. Without seeing the DAX it's hard to know what command generated it and what to recommend. Take heart though, it's something all of us have wrestled with and (mostly) overcome. You'll figure out what each command is returning.

Not to answer your original question, alas, but I'm curious about your forecast table and wondering if you would use PowerBI to generate those values instead of pulling them from a table you generated elsewhere. PowerBI really is a "reasonable ask" for what you want to do, and it will be rewarding (and save you tons of time) when you figure it out. I did something similar to create a pro-forma to forecast costs by month for a planned new laundry facility based on inflation rates and expected incremental capital and expense costs in future years. It's somewhat advanced to generate the date logic so that you're taking year 0 base costs, multiplying by 1+x% for the forecast period (e.g. 42 months ahead), and remembering to add in the incremental costs plus inflation that hit in month 34. But not excessively so. Each month we have variable costs (e.g. employee) based on the forecast volume of laundry and fixed costs on depreciation. Our investors want to see the overall cost per pound in each month, and what amount of cost is associated with each input (e.g. employee, transport, ...).
Master Excel Bundle

Excel contains over 450 functions, with more added every year. That’s a huge number, so where should you start? Right here with this bundle.

Forum statistics

Latest member

We've detected that you are using an adblocker.

We have a great community of people providing Excel help here, but the hosting costs are enormous. You can help keep this site running by allowing ads on
Allow Ads at MrExcel

Which adblocker are you using?

Disable AdBlock

Follow these easy steps to disable AdBlock

1)Click on the icon in the browser’s toolbar.
2)Click on the icon in the browser’s toolbar.
2)Click on the "Pause on this site" option.
Go back

Disable AdBlock Plus

Follow these easy steps to disable AdBlock Plus

1)Click on the icon in the browser’s toolbar.
2)Click on the toggle to disable it for "".
Go back

Disable uBlock Origin

Follow these easy steps to disable uBlock Origin

1)Click on the icon in the browser’s toolbar.
2)Click on the "Power" button.
3)Click on the "Refresh" button.
Go back

Disable uBlock

Follow these easy steps to disable uBlock

1)Click on the icon in the browser’s toolbar.
2)Click on the "Power" button.
3)Click on the "Refresh" button.
Go back