Not all columns retrieved on `new ColumnSet(true)` in a plug-in

Question

I'm building the following query. For some reason, it doesn't bring to me all the fields. I've checked the spelling and when I assign values to those field, I even switched the name, leading to an exception. So I know for sure that they exist and are used. I'm adding a pre-image to the update-step with all data, just to be sure.

QueryExpression request = new QueryExpression
{
  EntityName = "myLogicalName",
  ColumnSet = new ColumnSet { AllColumns = true },
  Criteria =
  {
    Filters =
    {
      new FilterExpression
      {
        FilterOperator = LogicalOperator.Or,
        Conditions =
        {
          new ConditionExpression("someField", ConditionOperator.NotEqual, someValue),
          new ConditionExpression("someField", ConditionOperator.Equal, somValue)
        }
      }
    }
  }
};

EntityCollection result = Service.RetrieveMultiple(request);

What can I be possibly missing?!

Answer 1

Its probably because; the field does not have a value or field level security is being applied.

As a side generally you should avoid using AllColumns = true

Answer 2

Setting the AllColumns property to true is essentially the same as doing a Select * in sql. The columns won't be adding to the ColumnSet, but they will be returned in the results of your query expression.