Scalar-Valued Functions

1. Overview

Similar to the SQL construct of scalar-valued functions. A Scalar-valued function in Cinchy is used to return a single value of any CQL data type. The function body can execute any JavaScript logic.

2. Using a Scalar-Valued UDF in CQL

Select a scalar value UDF as a column (Image 1).

Sample UDF

function demo(param1, param2) { 
    return param1 + ' ' + param2;
}

Sample Query

SELECT [Domain], [Name], demo([Domain],[Name]) as 'Full Name'
FROM [Cinchy].[Tables]
WHERE [Domain] = 'Cinchy'

Image 1: Using a Scalar-Valued UDF in CQL

Scalar-valued functions have to be invoked with a parameter, even if the definition of the function does not require a parameter. You can pass a string:

SELECT my_scalar('a') FROM [Cinchy].[Tables] WHERE [Deleted] IS NULL AND [Cinchy Id]=1

3. Using a Scalar-Valued UDF in a Calculated Column

Once it is confirmed that the UDF returns the expected result though a query, a calculated column can be include.

3.1 For Calculations

Depending on how intensive or live you want the calculation to be, choose whether to make it a live or cached calculated column.

Simply add your UDF to the calculated column (Image 2).

Image 2: Using a Scalar-Valued UDF for Calculations

3.2 As a Trigger

To use the UDF to trigger an action (ex. create a row in another table), it should be a cached calculated column. Here are a few scenarios to watch out for:

• Do not trigger when you do not have all the necessary fields

• Do not trigger when non-relevant data on the row changes

  • Make sure to appropriately insert and/or update in another table