Hierarchical filtering in tableau

 Selecting  the values in one filter if it is effecting in the other filter then such a kind of filtering is known as cascading filters this cascading filters are also known as hierarchical filters normally this cascading filters can be applied for the hierarchical data. if you  apply only relevant values on more than one filter means their filtering each other some time may resulting leads degrade the performance. so it is not good practice by applying only relevant values on two quick filters simultaneously at a time.

Calculations in tableau

   Normally each and every time in tableau it is not possible to obtain the meaningful output from the existing data field .some times we need to create the new field in the tableau known as the calculated field.this calculated fields can be obtain  by writing calculations this calculations contains data fields ,parameters,functions and optionally comments also as this calculated field are deriving from the existing data fields this calculated fields are also known as as derived fields.


   note 
 one calculated field can be used inside the second calculated field without restrictions.

Date functions in tableau

   date add function


             date add function takes the input as date and to  input date it will add the interval based on the             date part.


              syntax:

                    DATEADD(datepart,interval,input-date)
               where data part indicates month,year ,quarter ,day etc.



          example

                  Date add('month'3,,#8-nov-2014#)=8-feb-2015


       note 
             in tableau the date should be enclosed between the open# and the closed #


             in date functions always the datepart should be specified in the lowercase.



DATE DIFF


          date diff function finds the diff between two dates based on the datepart and optionally it will             takes the  'week start day also'.

 
                    syntax
                           DATEDIFF(datepart,start-date,end-date,[weeksstartday])



DATE NAME:

           the date name function takes the input as date along with the date part and it names that date                     part.


             syn

               datename('datepart',input-date,[week-start-day])


      
             
                example  datename('month',#8-nov-2014#)=nov



DATE TRUNK


              date trunk function reduce the accuracy of the input date based on the date part.


                  syn
                         datetrunc (datepart,date,[week-start-day])



                         datetrunc('month',#8-nov-2014#)=1-nov-2014



DATE PARSE


            The date parse function converts any string to the date based on the input format this function is available


            from tableau 8.2 based on the specified format tableau will convert the data.



                      syntax:


                            Dateparse(dformat,string) 



                       example

                           
                            Date parse("dd.mm.yyyy,'08.10.2014')= 8-nov-2014


 
today,now functions
         
                  today function gives the current date where as now function gives the current date+time.