I have a large text table (about 200k records) that's generated from a custom SQL query. I've added filters so users can limit the output, but the text table is still quite large, so rendering of the table is pretty slow. I know that I can limit the rows displayed using a calculated field like Index(). However, what if I want to limit the rows displayed to the user, but still enable them to pull the full dataset? In other words, lets say they filter by ID #123 and the text table has 5k records with ID #123. I want to display at most 100 of these records in the dashboard and if they need the complete raw data, they can pull the 5k into a crosstab. Currently, if I apply an Index to limit the rows displayed in the dashboard to 1k, they'll only be able to download 1k records to the dashboard.
Ultimately, the purpose is to make the raw data available, but make the experience using the dashboard a lot faster.
You could create a separate sheet purely for download. When downloading all of the records on the Detail shelf are exported - the fields don't need to be visible in the dashboard. Therefore you could create some form of dummy field - perhaps something simple like a SUM([Number of records]) - to display in the view with the remainder of the fields hidden on the Detail shelf. This means the view won't take an age to render but the fields will still export.
Related
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 have a table in BigQuery that has 35 million rows that I want to turn into a Tableau extract, but the number of rows is so great that it can't add all of them at one time. The solution I have come up with is to first the number of rows that are presented by the BigQuery view by only showing rows within a particular date range for a full extract and then after the extract is completed slowly increase the number of rows displayed by the view (by altering the where statement to only show particular rows) and then having Tableau perform an incremental extract based on the field containing the time stamp. That worked for a few of the incremental updates, but now I've run into a problem where Tableau Desktop says 'Required columns are not present in the remote data source. Perform full refresh of the extract', except that nothing in the data source or within tableau has changed other than the WHERE clause affecting the range of dates that the view presents. This was apparently a problem in Tableau 8, but I'm on Tableau 9.3. Anyone have any suggestions?
I'm not sure if this will be a solution for everyone, but the problem that I was having seems to have been caused by making connections to Google BigQuery per hour.
I'm using Tableau Desktop 9.0 on OSX. I have data (loaded from a local CSV file) that looks like this:
code,org,items
0212000AA,142,10
0212000AA,143,15
0313000AA,142,90
0314000AA,143,85
I want a chart that shows the number of items beginning with 0212 as a percentage of all items, for each organisation. (I mean as a percentage of the organisation's items - for example, in the above, I would like to show 0.1 (10/(10+90)) for organisation 142.)
I have been able to get part way there, by adding org to Columns, and SUM(items) to Rows. Then by adding a Wildcard filter on code, for starts with 0212.
This shows me the number of items starting with 0212, by organisation.
But what I don't know how to do is show this divided by the value of all items for the organisation.
Is this possible in Tableau, or do I need to pre-calculate it before loading my data source?
One way is to define a calculated field called matches_code_prefix as:
left(code, 4) = "0212"
You can also define a parameter called, say, code_prefix to avoid hard coding the prefix string:
left(code, 4) = code_prefix
And then show the parameter control for code_prefix to allow the user to interact with it.
If you use this new field as a dimension to separate SUM(items) according to those that match the prefix and those that don't, you can then use a quick table calculation to get the percent of total.
For example, you can place org on the Rows shelf and matches_code_prefix on the Columns shelf, and SUM(items) on the Text shelf to make a table. Then under the analysis menu, turn on grand totals for both rows and columns to see the behavior. Next, right click on SUM(items) and choose Quick Table Calc->Percent of Total. Tableau will display the percents of total in the table.
If you want the percent of total defined differently than the default, then right click on the measure again and set Compute Using to a different value such as matches_code_prefix in your case. It's usually better to set compute using to a specific field.
If you only want to display the value for the matching case, select the column header you don't want to see and choose hide. You can also turn off the grand totals from the analysis menu when you are done.
When you are confident in the values in your table, you can turn it into a bar chart for example by moving matches_code_prefix to the detail shelf and the measure to the Columns shelf.
--
The above is the drag and drop approach. If you prefer to hard code everything in a single calculated field that is calculated on the database side, you could instead define a calculation such as:
zn(sum(if matches_code_prefix then items end)) / sum(items)
Then set the default number format for that field to display as a percentage
I am trying to do a list report with about 40 columns(Dims+measure) but not able to get it right,
the requirement pushes the Tableau limitation by exploiting its limit to only 16 columns.
How can I get this done?
I read this
Here is my Tableau workbook with 16+ columns but no column header
Go to Analysis-->Table Layout -->Advanced and change the number in Rows and Columns as per your need.
You can't add more than 16 to this, but increase it to 16 (for identification).
So, save the Tableau file with extension .TWB. Then open this file in notepad.
Then search for the text: attr='row-levels'.
You will find something like:
<format attr='row-levels' value='16' />
<format attr='row-horiz-levels' value='16' />
Change the value of 16 to desired column numbers. Save the notepad file. Open it in Tableau.
The measures names and measures values special fields can help here and covers most use cases. (Using the measure names and values fields is likely a better choice than creating 40+ marks cards as you did in your posted example)
Put Measure Names on the column and filter shelves and measure values on the text shelf. Then add the measure fields you want to the Measures Values shelf. Then put the dimensions that you wish on the rows shelf.
A single field+aggregation can only be on the Measure Values shelf once, but a field can repeat with different aggregations -- so you can show the min, avg and max of a measure in 3 different columns.
As you mentioned, you can increase the max col and row headers up to 16 each via the Analysis->Table Layout->Advanced menu and panel. Beyond that point, adjacent columns will still display, just be coalesced for display.
Still you can have an apparently arbitrary number of fields on the measures values shelf, so can display as many columns of measures (data) as you wish, even though adjacent header columns for dimension (~category) get coalesced for display once you hit the header limit.
Tableau is optimized for summarizing data for efficient interpretation by humans, so displaying extremely wide tables of data is not the best fit for the tool (or a human reader frankly). Importing and exporting large tables is certainly possible.
At the 2015 conference I went to a session called "Use Tableau Like a Sith" and they showed us how to change the XML to workaround the 16 limit. Caveat being this is not supported.
Find the entries in the attached image and change their value to 40. In the screenshot, the Sith presenters were changing them to 36.
Here is a workaround for some data sets:
convert your fields from Dimension to Measure, and then
display using Measure Names / Measure Values, as #Alex Blakemore suggested.
For example, Boolean fields can be converted to numeric using INT().
PROS:
It is easier to change which fields to plot using Measure Names / Measure Values.
Faster performance, at least for some data sets.
CONS:
Often data sets have some fields that cannot or should not be converted to measure.
Not as easy or straightforward as changing Analysis > Table Layout > Advanced settings, or the xml-editing workaround suggested by #Cyndi1976.
There are Two ways:
Edit the saved .twb file and edit the Below xml code by opening the workbook with Notepad
<format attr='row-levels' value='16' />
<format attr='row-horiz-levels' value='16' />
Create 3 different worksheets each consisting multiple column but each worksheet consisting columns >16 and place them in single dashboard. So you will get one view with 40 columns.
A good way to do this is to create groups and filters. I'm sure, out of 40+ columns, a good number of them can be converted to either of the above, giving a neater look to your dashboard, making it easy to comprehend your data.
Let us assume you're creating a dashboard to show the overall split of mobile recharges for a company x.
One of the option is to have multiple columns; each for:
the mobile OS
OS version
service provider
recharge rank
Sub-category (Prepaid / Postpaid)
...
the easier and elegant way to reduce the number of columns is to populate a dropdown list with these values. Not only this will make the dashboard easier to comprehend, it will reduce the number of columns one has to refer to interpret the data and would also reduce the technical limitations imposed on the number of columns.
to create a group in Tableau:
include the fields in the result set i.e. use the column[s] in select statement.
select os, os_version, service_provider, rank, subcategory ... from schema.recharge_table [where...];
In the Sheets view of Tableau, right click on the field to create group. Let's create a split on subcategory.
Group the sub-categories, give them proper alias to be recognised easily.
Drag the Group to filter and you've successfully and elegantly reduced one column.
16 is the maximum limit for row/column labels in tableau table.
Put 20 columns on one sheet and 20 one the other dashabord. Drag and drop both sheets on to your dashbaord, and you should be having 40 columsn.
I have a problem with a BIRT report I'm working on where I have a nested table in the report. The outer table contains data to do with an item on an invoice, while the inner table contains stuff to do with price banding for labor charges. I've written a separate DataSet which gets the inner data, bound by parameters to data in the outer table. Now, when I preview the inner DataSet in BIRT using the defaults I've given it, it returns two rows of data for that bill number & item number - a normal rate & an overtime rate if you like. When I run the report in full over the same data, the outer table stuff is fine, but the inner table just repeats the same row over twice - it's just the first row repeating.
This is sorta what the table looks like in layout view:
Item Description Rate Quantity Item total
[item] [desc] [rate] [quantity] [total]
...where the price & quantity are in the inner table.
I'd have expected to see something like:
Item Description Rate Quantity Item Total
1 Callout $40 1 $40
2 Labor $30 4.5 $185
$50 1
but instead I get more like:
Item Description Rate Quantity Item Total
1 Callout $40 1 $40
2 Labor $30 4.5 $185
$30 4.5
...even though querying the database & previewing the inner data set based on the same input criteria show the expected result.
Has anyone else had experience like this? I have a hunch it's to do with bindings, but not sure what.
One way to get this behavior is by accidentally replacing a table-level binding with a column-level binding.
For example, define a table by dragging a data set into the report. Select the entire table (use the outline view, or select something in the table and then click on the "Table" button that pops up just below the grid.) Then go to the Binding tab. Note that the data set and column bindings are all filled in.
Now select just one field in the Detail row. On the Binding tab, note that the Data Set is blank, and no column binding is shown. Someone who is confused by this (as I was) might then edit the column's binding and specify the same Data Set that was used to create the table. If you do this you will only see a single value repeated in that column when you run the report. (I believe the overridden column is binding to a second instance of the data set, not the one the table is iterating over.)
Not sure your question can be answered withou looking at the data and the design. But it is important to note that the results you see in the dataset preview, and not neccisarly what you would see if the query was run fully. I have seen difference with 7 records returned. I thought as it was only 7 it would be the same on full run, but it's not. The preview is not just a top 500 query, it has some other (not sure what) filters also.
To problem solve if it is your query or your binding.
If you are using a SQL database. Run the SQL in a SSMS query and see if you get the same results you do when run in the innner table.
Altentively, create a new test report, copy over your dataset and use with a stand alone table.
I think I sorted it, & this is the most bizarre thing: On the child table I'd been deleting the header & footer row & just leaving the detail row in, in the layout view. Last thing today, just before I was going to go home, I tried again - deleted the table for about the 70th time that day, replaced it, re-did the parameter bindings all exactly as before, but this time I left the header row & footer intact. Clicked the preview tab, voila, all shows up correctly. So, since I didn't need the header or footer on the child table, I went into properties, clicked Hide this element, preview again - all good. No difference to the data bindings, no difference to mappings or anything else, no change to the data sets - the only difference was leaving the header & footer in place but hidden.
Contemplating making a bug report, tbh.