Keywords

Words described next with an '_' before them are system keywords with specific meaning for VDMS. Their usages are listed in the command examples as appropriate.

_ref: Local id for reference (can be defined in one call and reused in following calls like Connect). Valid within a single transaction. This must be a number in the range [1,10000].

_date: VDMS can parse certain date formats but the way to specify that in JSON is through a string. So in order to specify date properties, we provide string value but prefix it with this keyword. Example in the properties block below. The supported format for the date is: "Mon Aug 7 12:59:24 PDT 2017". One Example of a query using this keyword:

"AddEntity" : {
    "class" : "Visit",
    "_ref": 4567
    "properties" : {
         "start": {"_date": "Mon Aug 7 10:59:24 PDT 2017"}
         "end":   {"_date": "Mon Aug 7 12:59:24 PDT 2017"}
         }
}

_blob: Similar to date, we want to distinguish between regular strings and blobs. Hence this qualifier. This is to specify a property that goes in the metadata database. In case of images etc, we will talk about blobs but those would be provided as or returned along with the string json.

_globalid: All entities including images, and collections have a global system id associated with them.