exists
Checks whether data exists within this JSON expression at the specified path.
Parameters
path
String(s) representing JSON path/keys that match fields to check for existing data. If none are provided, the root context item '$' will be used by default. Note: Multiple path arguments are not supported by all vendors; please check the documentation.
optional
String representing any optional vendor-specific clause or argument. Note: optional function arguments are not supported by all vendors; please check the documentation.