ARDI Selectors
Selectors are a new method of searching for and choosing ARDI assets.
They're smaller, simpler and faster to write than AQL statements, although slightly less flexible. Selectors are often used when choosing/specifying assets. They will be appearing in more ARDI plugins as time goes on, and can also be used in queries AQL using the SELECTPOINTS and SELECTASSETS functions.
They are loosely inspired by CSS Selectors, which are used in web-pages to help select the various components of a web page.
What A Selector Does
A selector is a type of search - it hunts through your ARDI assets to find any that match the criteria you've written in your selector.
These can be used whenever you need to quickly address a number of assets at once - such as when attaching alerts, in security rules or when creating charts and visualisations.
Selectors are usually used in one of two ways - to find an asset (or assets) in your ARDI database, or to validate an asset to see if it matches some type of search criteria.
Selector Syntax
A selector is made up of rules which are combined together to search for specific assets. Most rules have a symbol at the start to control what you're searching for.
Asset Name Rules
A rule with no symbol at all is an asset name rule - it searches ARDI for any assets with that name, ID or data value.
The selector…
Finish Oven
…would find any assets named 'Finish Oven'.
Asset Type Rules
A rule with the '@' symbol at the start is an asset type rule - it searches ARDI for all assets of a particular type.
The selector…
@Temperature Sensor
…would find all assets with a type (or that are a sub-type) of 'Temperature Sensor'.
Property Name Rules
A rule with a period (.) at the start is a property name rule - it searches ARD for all assets that have a particular property.
The selector…
.Internal Temperature
…will search for all assets that have the 'Internal Temperature' or 'Temperature - Internal' property.
Using Relationships
You can also use relationships in your selectors.