Sometimes when we create reports we define the sort order of the data within the report itself. This allows the user to pick and choose data based on the sort order that make most sense when viewing the data. Notice how the second column ( which is the column order or position of the column within a table is not ordered within the report)
Let us begin by first making the column sorted in asc order
Right click the tablix control and select Tablix Properties. Go to the Sorting option on the left hand side menu and Press Add
In the text box “sort BY” enter the name of the column on which the sort order is determined. In the Drop down list for Order select A to Z for Asc order.