Power BI — Understanding DAX Syntax

DAX Syntax

Dax Syntax is like writing functions in Excel or writing a statement in SQL. The same parts appear every single time.

First, we have a name for a particular measure that we’re providing.

In this case, it’s total sales. Remember, no spaces. And we have an operator.

In this case, and in most cases, the equal sign, followed by the name of the DAX function.

Now, remember that sum is a really short word. You might think, well that really wasn’t all that helpful, but some of the functions, so to speak, are more complex, longer names, and more keystrokes. So it’s nice to have this intellisence kick in, but I particularly appreciated that after I typed the sum function and hit tab, I got open parentheses.

Then a list of table names and columns that I could be choosing from. And again, that’s being provided for me by intelligence.

Note that within parentheses, the table name isn’t in quotes like it may be in some other formula languages. Instead, the table name appears and then an open bracket, the name of the column, a closed bracket, and then the parentheses then are enclosing the arguments for the Dax sum function.

We’re indicating that in this particular table when we say TotalSales, we mean to take the sales amount and add them all up.

Sum all the values in the SalesAmount column. And that’s how we do it using Dax Syntax.