docs: public QueryBuilder<T, ID> groupBy(String columnName) {
  		FieldType fieldType = verifyColumnName(columnName);
  		if (fieldType.isForeignCollection()) {
  			throw new IllegalArgumentException("Can't groupBy foreign collection field: " + columnName);
  		}
  		addGroupBy(ColumnNameOrRawSql.withColumnName(columnName));
  		return this;
  	}