I have my tableau workbook and I'm currently counting by a field called ID - COUNT([Id]) - while this is great, on days with no activity my dashboard doesn't show ANYTHING and I want it to show zero if there was no activity - so I do I change this to count but also replace null with 0 (zero)?
First make sure you understand what Count([ID]) does. It returns the number records in the data source that have a non-null value in the column [ID].
Count() never evaluates to null. But if you have no rows at all in your data after filtering, then you'll get an empty result set -- i.e. view data will not have any summary data to show at all - whether null or zero.
Wrapping COUNT() in a call to ISNULL() or ZN() won't help in that case.
The solution is to make sure you have at least one data row per day, even if all other fields besides the date are null. Aggregation functions ignore nulls so padding your data like this should not disturb your results. The simplest way is to make a calendar table that has one row per day with nulls in most columns. Then use a Union to combine the calendar with your original data source. Then Count(ID) will return zero on days where there are no other records besides the calendar entry.
You can also get similar results using data blending, although with a bit more complexity.
Related
I am trying to add a column to a collection by multiplying the 0.9 to existing database column recycling. but I get a run time error.
I tried to multiply 0.9 direction in the function but it is showing error, so I created the class and multiplied it there yet no use. what could be the problem?
Your error message is telling you what the problem is: your database query is using GROUP BY in an invalid way.
It doesn't make sense to group by one column and then select other columns (you've selected all columns in your case); what values would they contain, since you haven't grouped by them as well (and get one row returned per group)? You either have to group by all the columns you're selecting for, and/or use aggregates such as SUM for the non-grouped columns.
Perhaps you meant to ORDER BY that column (orderBy(dt.recycling.asc()) if ascending order in QueryDSL format), or to select all rows with a particular value of that column (where(dt.recycling.eq(55)) for example)?
I have a calculation and it outputs multiple values. Then I am creating a table on those values. For example, in below data my formula is
if data is 1 then calculation is `one`
if data is 2 then calculation is `two`
if data is 3 then calculation is `three`
as three doesn't really appear in the output, when I create a table, three is not displayed. Is there any way to display it?
I tried table layout >> show empty rows and columns and it didn't work
data calculation
1 one
2 two
Tableau discovers the possible values for a dimension field dynamically from the query results.
If ‘three’ does not appear in your data, then how do you expect Tableau to know to make a column header for that non existent, but potential, value? It can’t read your mind.
This situation does occur often though - perhaps you want row or column headers to remain stable, even when you change filters in a way that causes some to no longer appear in the query results.
There are a few ways you can force Tableau to pad ** or **complete a domain:
one solution is to pad your data to make sure each value for your dimension field appears in at least one data row.
You can often do this easily by using a union to append some extra rows to your original data. You can often add padding rows that don’t impact any results by leaving all your Measure columns null since nulls are ignored by aggregation functions
Another common solution that is a bit more effort is to make what is known as scaffolding data source that is not much more than a list of your dimension members. You can then use that data source as a primary data source with data blending, making your original data source secondary.
There are two situations where Tableau can detect the absence of data and leave space for it in the visualization automatically
for numeric types, you can create a bin field that will automatically pad for missing bins
similarly, date fields can show missing values because, like bins, Tableau can tell when a month doesn’t appear in the data and leave room for it in the view
I'm trying to annualise my data in tableau, but get an error in the Calculated Field.
"Cannot mix aggregate and non-aggregate arguments to function"
my formula is
sum(profit)/month(selected date) *12
How do I get an integer for the current month? That seems to be the problem, it tries to aggregate the month as well.
Thanks.
Short answer: wrap the call to month in a call to min() -- which works well if you have MONTH([selected date]) on the visualization as a dimension.
There are three types of calculated fields in Tableau:
row level calculations which act on a single data row. They can read from values of other fields in the same row and return a single value per row.
aggregate calculations which act on a partition or block of data rows. They can reference the result of aggregating the values for a field across the entire partition, using a an aggregate function like SUM() or MIN().
table calculations which act on an entire table of aggregated results.
You can't mix and match. Everything in a calculated field must be all at one level or another -- either all referenced fields must use aggregation functions (for aggregate calculated fields) or no referenced fields must use aggregation functions (for data row level calculated fields).
Hence the error message you saw.
Sometimes you know that all values for a field will be the same in a partition based on your visualization, so the aggregation function seems unnecessary. But Tableau still requires you to be explicit about how to turn a block of values into a single value, because the calculation must be defined even when the visualization is partitioned differently. In these cases, you can use min(), max(), avg(), or perhaps attr() because they all return the same value for a list of identical values.
The first two types are typically executed on the server (i.e. they are implemented by Tableau emitting SQL to send to the database server). Table calculations are executed by Tableau on the client site to post-process the results from the database server.
Table calcs are the most complicated type, but can be very useful. Explaining them is a post for another day.
I am developing an SSRS 2008 report. I created a tablix, however, when I view this report one of the rows has zero entries. This row is not showing in the output. How can I make it show regardless of values so that it will just show "0" otherwise?
This was the expression I used for it:
=iif(CountDistinct(Fields!Client.Value)=0 or
isnothing(countdistinct(Fields!Client.Value)),0,
CountDistinct(Fields!Client.Value))
And I have tried grouping on different fields and also filtering on another field, but none of these make it appear when there is no data.
I think that the best you can do is ensuring that the dataset you are using has the record you want, even if it is null. For example, if you are grouping months, and you want all 12 months to appear in your tablix, then you need to make those months to exist in your dataset even if they have null values for all the other columns.
I have the following issue: I have a report that uses a Dataset as its datasource. The dataset has two tables, one would be the main table, say Employee, and the second table is EmployeePaycheck, so an employee can have several paychecks. I can compute the sum of a column in the second table, say paycheckValue, but what I can't seem to do is also add to this computed field the value of some additional fields in the Employee table, such as ChristmasBonus or YearlyBonus, to see how much the employee was paid at the end of the year.
Without knowing more information on this it will be difficult to answer, but I'll give you a couple things to look for.
First, I would make sure that the fields are of a similar type that will allow for a summary. For example, if one is a string then a summary wouldn't be able to be done without casting or convertingthe value to a number. I'm assuming that the fields are probably number or decimal columns so that is probably not the case.
I'd also check to make sure that none of the values that you are trying to sum are null. I haven't tested this, but I believe that it will not sum correctly if one of the rows has a null value. In this scenario you should just be able to use a formula field to check for the null and if the field is null return 0 instead. Then you can use the formula field in your calculations instead of the field itself.
If neither of these are the case please provide a little more info how you are computing the fields and what is happening when you do it.
Hope this helps.