Data requirements
This topic covers the input data requirements for NLG Apps and Arria Answers. If you get unexpected results, please check that your data meets the requirements stated below.
The topic is organized as follows:
Note
The topic assumes the data is being uploaded in tabular form (either a CSV or XLSX file).
Measures
A measure is a numeric, quantitative field in your data. Measures in the sample dataset include Sales and Profit.
The requirements for measures are:
Decimal numbers must use a period for the decimal separator.
If using thousand grouping separators, they must be commas.
Aggregation type must be one of the following: Sum, Average, Minimum, Maximum, or Count*.
Measures created in Tableau using an aggregate calculation are also supported, provided that further aggregation by Sum or Average is valid. Such measures are displayed as AGG(MeasureName) on shelves and cards in the worksheet. For example, for a measure named Margin:
Tip
*Arria Answers does not support the Count aggregation type.
See Query types for guidance on which aggregation types are required by each type of query.
Tip
Not all aggregation and entity type combinations are supported by every NLG app. See the NLG Apps Directory for app-specific guidance.
Dimensions
A dimension is a categorical, qualitative field in your data. Dimensions in the sample dataset include Country and Product.
The values in a dimension field are known as dimension instances. For example, Canada and Germany may be instances of the Country dimension.
Categorical dimension values will typically be textual or alphanumeric rather than purely numeric; however, purely numeric outputs are allowed.
In Arria for Tableau, the term time dimension refers to a special type of dimension that contains date values. Time dimensions are used to analyze your data by day, month, quarter, or year. The data requirements for time dimensions are described below.
Important
Arria for Tableau supports discrete dimensions only. If the selected worksheet contains continuous dimensions, Arria for Tableau returns an error message or inaccurate narrative. See the Tableau documentation for guidance on discrete vs continuous dimensions.
Time dimensions
A time dimension is a particular type of dimension that contains date values. You can use time dimensions to analyze your data by year, quarter, month, or day.
This section provides guidance on valid field names and data values when using time dimensions with NLG Apps and Arria Answers.
Important
Arria for Tableau supports discrete dimensions only. If the selected worksheet contains continuous dimensions, Arria for Tableau returns an error message or inaccurate narrative. See the Tableau documentation for guidance on discrete vs continuous dimensions.
Tip
When Arria for Tableau identifies an attribute as a time dimension, the Entity Type field is automatically set to DateTime. If necessary, you can set the entity type in the NLG Apps wizard or the Arria Answers wizard.
There are two ways to store dates in your raw data:
Date columns
Date columns in your raw data can be used in two ways: as a Tableau date hierarchy, or as a date field.
Tableau date hierarchy
Tableau automatically creates a hierarchy of data fields from date columns in your raw data. When working with date hierarchies and creating a worksheet for use with Arria for Tableau, click the + icon to drill down to the DAY(Date) level, as shown here:
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Important
Each field in the date hierarchy is counted as a single time dimension. This is important to know when considering the minimum number of time dimensions required by each NLG app. See the Data Requirements section for each app for further information (NLG Apps directory).
Supported field names
Arria for Tableau supports the date hierarchy field names used by Tableau: YEAR(Date), QUARTER(Date), MONTH(Date), and DAY(Date).
Single date field
If you prefer to use a single date field instead of a hierarchy of date fields:
Drag the Date field to the Rows or Columns shelf in your worksheet, click its context menu, and select Exact Date.
Click the Date field's context menu again and change the dimension type to Discrete. Continuous dimensions are not supported by Arria for Tableau.
See the Tableau documentation for more information.
Supported field names
A single field containing date values must be named as follows:
Naming Rule | Example Column/Attribute names |
|---|---|
*date* |
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The asterisks (*) are wildcards that represent one or more spaces, hyphens, or underscores. These rules are case-insensitive.
Tip
You can use the Alias field in the NLG Apps wizard and the Arria Answers wizard to override date column/attribute names and comply with the naming rules.
Supported date formats
The following date formats are supported:
Pattern | Example Values |
|---|---|
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Date components across multiple columns
An alternative to a single date column is to spread your date components (year, quarter, month, day) across multiple columns.
NLG Apps and Arria Answers use the following date components:
Years
Supported field names
A single field containing year values must be named as follows:
Naming Rule | Example Field Names |
|---|---|
y |
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*yr* |
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*year* |
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The asterisks (*) are wildcards that represent one or more spaces, hyphens, or underscores. These rules are case-insensitive.
Tip
You can use the Alias field in the NLG Apps wizard and the Arria Answers wizard to override date column/attribute names and comply with the naming rules.
Supported values
A year value must be a two-digit or four-digit number (for example, "22" or "2022").
Quarters
Supported field names
A single field containing day values must be named as follows:
Naming Rule | Example Field Names |
|---|---|
q |
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*qt* |
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*qtr* |
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*quarter* |
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The asterisks (*) are wildcards that represent one or more spaces, hyphens, or underscores. These rules are case-insensitive.
Tip
You can use the Alias field in the NLG Apps wizard and the Arria Answers wizard to override date column/attribute names and comply with the naming rules.
Supported values
A quarter value can be given in alphanumeric or numeric form:
Quarter | Example Alphanumeric Values† | Example Numeric Values |
|---|---|---|
Quarter 1 |
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Quarter 2 |
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Quarter 3 |
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Quarter 4 |
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† Any combination of the strings "Q", "Qt", "Qtr", and "Quarter" plus a number, with or without spaces, is acceptable for alphanumeric values. Therefore, "Q4", "Q 4", and "4Q" are equally valid. Also, any mixture of cases is acceptable. Therefore, "QUARTER 1" and "qUARTER 1" (to give two alternatives) are valid alternatives to "Quarter 1".
Months
Supported field names
A single field containing month values must be named as follows:
Naming Rule | Example Field Names |
|---|---|
m |
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*mon* |
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*mth* |
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*month* |
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The asterisks (*) are wildcards that represent one or more spaces, hyphens, or underscores. These rules are case-insensitive.
Tip
You can use the Alias field in the NLG Apps wizard and the Arria Answers wizard to override date column/attribute names and comply with the naming rules.
Supported values
A month value can be given in text or numeric form:
Month | Example Text Values† | Example Numeric Values |
|---|---|---|
January |
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February |
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March |
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April |
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May |
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June |
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July |
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August |
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September |
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October |
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November |
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December |
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† This requirement is case-insensitive, so "JAN", "JAn" and "jan" are valid alternatives to "Jan".
Days
Supported field names
A single field containing day values must be named as follows:
Naming Rule | |
|---|---|
d |
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*day* |
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The asterisks (*) are wildcards that represent one or more spaces, hyphens, or underscores. These rules are case-insensitive.
Tip
You can use the Alias field in the NLG Apps wizard and the Arria Answers wizard to override date column/attribute names and comply with the naming rules.
Supported values
A day value must be a one-digit or two-digit number (e.g. 5 or 05). Ordinal numbers (e.g. 5th) are invalid.
