Model Functions

Field Description

Field Name

Name. Name of the function.

name

Description. Description of the function.

description

Input Format. Input format of the function. See format section for details.

inputformat

Output Format. Output format of the function. See format section for details.

outputformat

Help. Detailed description of variable.

help

Group. Variable group, or NULL if variable does not belong to any group.

group

Permissions. Permission level in the model context (or a context the relative model is attached to, or an instantiable model's instance context) required to execute the function.

permissions

Type. Defines function implementation type. The following types are supported:

• Java Code. Function implementation is represented by a Java class implementing a special interface containing an "execute function" method.

• Expression. Function implementation evaluates an Iotellect Expression having function input as a default table. Expression should evaluate to a table that  represents function output.

• Query. Function implementation executes an Iotellect query using input table cell values as query parameter values. Query results table represents function output.

type

Implementation. Available if Type is set to Java Code. Source code of Java class that implements the function body, i.e. does something the function is supposed to do. See defining and implementing functions for details.

implementation

Expression. Available if Type is set to Expression. An Iotellect Expression to evaluate during function execution.

expression

Default Context

• For an absolute model: the model context itself

• For a relative model: a context the relative model is attached to

• For an instantiable model: a model instance context

Default Data Table

Function input data table.

Default Row

0

Environment Variables

Standard variables only.

Query. Available if Type is set to Query. An Iotellect Query to execute during function execution.

Query text can refer function parameters using ? character, for example:

SELECT * FROM users.*.devices.*:temperature AS tpr WHERE tpr.temperature$celsius > ?

Number of ? parameter references in query text should match number of cells in function input table. First ? parameter reference will be filled by value of first column in the first row of the input table, second parameter value will be taken from the second column, and so on.

query

Concurrent. Enables execution of function on every call in separate environment. So you can call the same function with different input parameters at the same time. In this case they will work independently in parallel.

concurrent

Plugin. ID of a server plugin that defines the model. Required if function implementation should access plugin's internal Java classes.

plugin