I am wondering if there is a way to add unit (m,ft etc) in a column of numbers in a attribute table in QGIS. I want to do this so when I post the text the units can be posted as well. I am working with pressure data so i would like to the Kpa after the number.
No, you can't store UoM (units of measure) in a numerical field. UoM is text, which is not compatible with the numerical format. It's common practice to include the UoM in the field title, eg instead of calling a field "Area" call it "Area_ac" (for acres), "Area_ha" (for hectares) or "Area_sqm" (for square meters).
If you want the UoM stored in each field, you can create a new field in text(string) format, and copy over the values from the original column. Because this is a text field storing mixed numbers and text values, you won't be able to do mathematical functions, not even with the
to_int() function to convert a string to an integer.
If you simply want to display the numerical field with UoM, say as a label, you can use the expression builder to add UoM to the label. Eg, with a field called "Area_sqm", label with this expression:
"Area_sqm" || ' sq m'
concat("Area_sqm", ' sq m')