Range values in Tableau - tableau-api

I want to visualise the below excel table in Tableau.
When adding this table to Tableau it shows Salary values as String and thus under Dimension Tab and not under Measure, thus cannot make proper graph from it.
How to convert this Salary range values to Int ?

As #Alexandru Porumb suggested, the best solution is to have a min_salary column and a max_salary column — unless you really have the actual salary available which is even better.
If you don’t want to revise the incoming data, you can get the same effect using the Split() function in a calculated field from Tableau to derive two integer fields from the original string field.
For example, you could define a calculated field called min_salary as INT(SPLIT([Salary], ‘-‘, 1)). Split() extracts part of a string based on a separator string. Int() converts the string to an integer.

You could simplify the way it sees the data and separate the salary column into Min and Max, thus you wouldn't have the hyphen that makes Tableau consider the entry as a string.
Simplistic idea, I know but it may help until a better solution will be provided.
Hope it helps

Related

ADF String to Decimal return NULL value

I have an imported CSV file with string values.
In this file there are amounts, of which several lines equal 0,00
I want to create a TotalCA column by adding several fields in my table and convert it to a numeric value.
I use the toDecimal function and the values are all returned NULL and the created column is grayed..
I have done a lot of research and I can't find a solution. Can you help me?
Thank you
Lea
I made an example csv data if I understand you correctly:
Like you said, some rows are enriched with values greater than 0, and others contain "0.00" when it is a zero value. Actually, the row data contains different data type, int and decimal.
For these reason and as I tested, no matter toDecimal(), toFloat() or toDouble(), all of the functions don't work. I use Derived column expression to do the data conversion.
We can't keep these data and only can choose one type of them. If you choose the decimal or float, other rows data would be converted to '11.0', I think that also doesn't you want.
Source Projection: I preset the column type to double:
(Decimal can't keep '0.00', it only returns '0')
In one word, the only way is that use String data type to keep the data. And also use String data type to receive the data in sink dataset.
HTH.
Thank you all for your answers.
Here is my CSV file
If I go to the Source Projection module and change the type of my column LFC1_UM01S to decimal this is what I get:
Why are some values considered as NULL?
To decimal column

In PostgreSQL, is it possible to have a default format for real columns?

In PostgreSQL, I have a column with people's height in meters. If the height is, say 1.75 m, it shows properly, but if the height is 1.70 m, it shows as 1.7. I would like to have this already formatted to two decimal places, showing as 1.70 without formatting in each and every SQL call. Can I specify this in the table creation? Or a stored procedure, or something? I've seen a few things about timestamps, but not for real fields. Knowing how to format the decimal point as a colon (1,70) would be a plus.
Basically, presentation and "cosmetics" are the job of the application, not the database.
Having a default number of decimal places for floats would also create a problem, because the data returned by the database would not be the actual data in the column. So if you did a SELECT and it returned a value of 1.75, then if you searched for this value, you might not find it because the actual value stored was not 1.75 but 1.7499999999 and it was only rounded for display.
Potential solutions:
If you want to store a specified number of digits, use NUMERIC. This will solve the 1.7499999999 problem above. If you use NUMERIC, when doing a SELECT you get the actual contents of the column.
In your app, if you use an ORM, use a Decimal (or similar) type for the column with the appropriate settings so it displays the way you want.
Or create a view with the format applied to the column, but in this case if you want the trailing zero, the type will be text and not float, and it will not be searchable unless you create an extra index on it.
Generated column with the number formatted as you want, maybe easier than a view

Tableau calculated field that refers to its own previous lagged (-1) value to calculate

I need help on a basic calculation that I'm unable to figure on Tableau.
I am trying to setup a calculated field that has dependency on its previous value to calculate its current value. Here is a simple example from Excel -
Sample Exhibit
As you can see, each value in a row is dependent on its previous value and multiplied by a constant.
In Tableau, when I'm trying to create a calculated field, it is not letting me refer to itself (-1 lagged value) in the code. I'd appreciate any help on how this can be resolved. Thanks in advance!
Tableau can do this client side with a table calc. You’ll have to learn how table calcs operate from the help- especially partitioning and addressing. Then you can use the function Previous_Value() to refer to the previous value. Practice on something simple first to make sure you understand how previous value() works. Hint, the argument to that function doesn’t mean what most people assume it means
If you want to perform this calculation server side instead, then you’ll need to use custom SQL so you can specify an analytic aka windowing query
Check the LOOKUP field to get the value from the preceding row. For example: LOOKUP(SUM([Value]),-1)
https://help.tableau.com/current/pro/desktop/en-us/functions_functions_tablecalculation.htm#lookupexpression-offset
You may need to make yourself familiar with the Table Calculation partitioning if not getting the expected result.

Rounding to a variable number of decimal places in SSRS

I am trying to find a way to round a field in SSRS to a dynamic number of decimal places. I know I can format it dynamically, and it may eventually come to that, but many of my users are going to take this report directly to Excel and are going to want to have actual numeric fields.
My t-SQL code includes these declared variables:
NumLong01 DECIMAL(23,8)
, NumLongDP01 INTEGER
The first set of entries in this table is for headers and rounding parameters. So I add values for these two as:
NULL
,4
and then I add the actual table values as:
543210987654321.87654321
,NULL
That way I can put a whole series of numbers into the table but they all have to be formatted the same way.
Running this query yields:
When I go to ReportBuilder, my field has this expression:
=Fields!NumLong01.Value
If I want to format a certain number of decimal places, I can just do this:
=Round(Fields!NumLong01.Value,2) or some such. What I tried to do, though, was to make it dynamic:
=Round(Fields!NumLong01.Value,First(Fields!NumLongDP01.Value, "DataSet1"))
This ended up rounding to 0 decimal places. I subsequently learned--by just using the second half in my field--that this was a NULL value. So I tried Sum instead of First--again, just in my field--and got the 4 that I expected. Great, so now I had my number, and I just put that in as my rounding:
=Round(Fields!NumLong01.Value,Sum(Fields!NumLongDP01.Value, "DataSet1"))
Only problem is, this yields an error. Next I asked myself if maybe it wasn't seeing this as a number for some reason. So i just added it onto my field. No problems. So I really don't know what it's doing. Is it thinking that this field might become so long that it will round to an illegal number of decimals places?
Now, I can do this:
=IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 8,Round(Fields!NumLong01.Value,8),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 7,Round(Fields!NumLong01.Value,7),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 6,Round(Fields!NumLong01.Value,6),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 5,Round(Fields!NumLong01.Value,5),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 4,Round(Fields!NumLong01.Value,4),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 3,Round(Fields!NumLong01.Value,3),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 2,Round(Fields!NumLong01.Value,2),IIf(Sum(Fields!NumLongDP01.Value, "DataSet1") = 1,Round(Fields!NumLong01.Value,1),Round(Fields!NumLong01.Value,0)))))))))
...and that works. But it seems like such a ridiculous way to go about it.
I'm also comfortable passing only rounded numbers out of t-SQL. But then I run into the problem of showing only a certain number of decimals on the report, because in the number formatting it doesn't allow for a dynamic number of decimal places for some reason.
Any ideas would be appreciated.
This isn't an exhaustive list of ways to accomplish dynamic rounding or number formatting as you can achieve this using custom code in the report or by adapting your dataset's SQL query.
Using Rounding:
The first set of entries in this table is for headers and rounding parameters. That way I can put a whole series of numbers into the table but they all have to be formatted the same way.
To avoid building expressions in your report that require aggregate functions such First and Sum and generating a blank row that you then have to remove, consider just entering the number of decimal places for every row instead of using a header row. The costs (storage and expression evaluation) are low even if it seems redundant.
This means that instead of using: =Round(Fields!NumLong01.Value,First(Fields!NumLongDP01.Value, "DataSet1")) you can use =Round(Fields!NumLong01.Value,Fields!NumLongDP01.Value) either as an expression or as a calculated field in DataSet1 or whatever your dataset is called.
Using Number Formatting:
But then I run into the problem of showing only a certain number of decimals on the report, because in the number formatting it doesn't allow for a dynamic number of decimal places for some reason.
You can define custom formatting for the NumLong01 field in the report and make it dynamic using an expression to build your custom formatting string.
Open the Text Box Properties for the NumLong01 textbox or tablix field
Open Number tab and select Custom from the Category list
Click the fx button and use the following expression ="0." + StrDup(First(Fields!NumLongDP01.Value, "DataSet1"), "0")
Using your example data, this expression would produce the custom formatting string 0.0000 which changes 543210987654321.87654321 to 543210987654321.8765. For your information, StrDup duplicates the specified string X number of times.
In cases where the fractional part of the number is less than the decimal precision required, this formatting string will pad it with 0s. If that's not desired, change the string to be duplicated to "#" like so: StrDup(First(Fields!NumLongDP01.Value, "DataSet1"), "#").
You can also use this method as a calculated field in the dataset but only if you have removed the header row and are entering the decimal places for every row as mentioned earlier. This is because you can't use the aggregate function in the calculated field expression.
To do this, add a calculated field to your dataset with the expression: =Format(Fields!NumLong01.Value, "0." + StrDup(Fields!NumLongDP01.Value, "0"))

add extra column value to a column sum

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.