Concepts → Incorta Table Formula Column
With the Analyzer, you can create an Incorta Table for a physical schema. An Incorta Table represents the materialized result of an Listing table or Aggregated table visualization. A load of an Incorta Table persists data to shared storage as Direct Data Mapping (DDM) files and not as Apache Parquet files.
You can only add a formula column to an Incorta Table using the Analyzer. It is not possible to add a formula column to an Incorta Table using the Table Editor.
The name property is only editable in the Analyzer. The default name is New Formula. You can return to the Analyzer to edit the column name. While in the Analyzer, double click the name of the formula column pill to edit the name. The label for the column will be automatically assigned the same as the column name.
Formula columns can be assigned as measures in a Listing Table visualization. Formula columns can be assigned as grouping dimensions and measures for Aggregated Table visualizations.
After creating a formula column using Formula Builder, in the Analyzer, the following properties are available in the Table Editor:
|Show in Analyzer||checkbox||Select if the column is displayed in the Analyzer tool||Select or deselect checkbox|
|Name||read only||The column’s name; used in the fully qualified name of the column.||Valid characters: A-Z, a-z, 0-9, $, _
Name must begin with a letter character
|Label||read only||A user friendly name. See NOTE below on editing Label.||utf-8 md valid characters, including emoji 😀|
|Type||read only||The Incorta Data Type of the column. See below section on type casting.||Integer, Double, Long, String, Date, Timestamp, Text, and Null|
|Function||drop down list||Select the Incorta Function of the column||Key, Dimension, or Measure|
|Encrypt||drop down list||Select if the column is encrypted in shared storage||True or False|
A formula expression returns a scalar value or array of values. These values are of a specific type. A formula expression can consist of builtin-functions, variables, and referenced columns.
A referenced column has a fully qualified name. Here are the possible types of referenceable columns in a runtime business view formula expression:
Using the Analyzer tool, you create the formula expression for a formula column in the Formula Builder.
The Formula Builder supports the following built-in functions for an Incorta Table formula column:
|Aggregation||Functions that accumulate data to a summary value||average, count, distinct, max, median, min, or sum|
|Boolean||Functions that evaluate to True or False||and, between, contains, endsWith, in, inList, isNan, isNull, like, not, or, startsWith|
|Conditional Statement||Statements that return a value based on the evaluation of a parameter||case, decode, and if|
|Conversion||Functions that convert the Incorta Data Type of a parameter. In addition, functions that manipulate Timestamp and Date values for different return values.||day, double, monthName, parseDouble, string, toChar, and year|
|Filter||Functions that specify a subset of data items||firstVersion or lastVersion|
|Miscellaneous||Functions with assorted uses||descendantOf, lookup, rowNumber, and schemaRefreshTime|
|Arithmetic||Functions that take one or more values and return a single value||abs, ceil, exp, floor, max, min, mod, rnd, round, sqrt, and trunc|
|Date||Functions that manipulate Timestamp and Date values||addDays, date, month, removeTime, weekday, and year|
|String||Functions that return string values or return values based on string parameters||bin, concat, find, ifNull, repeat, rTrim, and upper|
|Analytic||Functions that compute values over a group of rows and returns a single result for each row||denseRank, index, or rank|
Incorta will assign the Incorta Data Type of a formula column based on the output data of the formula. If you need to change the Incorta Data Type of the column you will need to convert the type using casting. You can cast the output of a formula using built-in conversion functions, such as int(), in the Formula Builder.
Formula columns have some specific capabilities in regards to the kind of columns, schema, and views they can reference in their formula expressions. Below is a table of the referencing capabilities of Incorta Table formula columns:
A data backed column references data that persists to shared storage.
|Schema/Table Type||Column Type||Referenceable||Note|
|Business Schema View||Data backed column||Yes|
|Business Schema View||Formula column||Yes|
|Incorta View||Data backed column||No|
|Incorta View||Formula column||No|
|Physical Schema||Data backed column||Yes||Can be within the same schema or a table from a joined schema.|
|Physical Schema||Formula column||Yes||Can be within the same schema or a table from a joined schema.|
|Incorta Table||Formula column||Yes||Can be within the same schema or a table from a joined schema.|
In the Formula Builder, in the Functions and Variables panel, certain variables are referenceable in the formula expression. Some types of variables all users have access to and other kinds of variables are subject to Discretionary Access Control (DAC).
Here are the various categories of variables:
- System Variables: Predefined variables within Incorta that return a value as a defined type.
- External Session Variables: Variables that query an external data source when invoked. Values returned as string.
- Internal Session Variables: Variables that query data within a schema. Values returned as string.
- Global Variables: A static variable available to all tenant users that return a value as a defined type.
Formula expressions in an Incorta Table can reference the following variables:
|External Session Variable||No||Referenceable in the Analyzer for the Incorta Table. A table load will succeed. In the Analyzer for an Insight, the formula column will show as #ERROR.|
|Internal Session Variable||No||Possible deleted data error will occur at table load.|
|Global Variable||No||Not supported in 4.9 or earlier releases|