At the moment, users will only be able to fetch SDC statements via the data extension service for properties which are entity-valued (such as "depicts").
SDC also relies on other properties, such as "relative position within image (P2677)" (string), "inception (P571)" (date), "coordinates of the point of view (P1257)" (geographical coordinates) and probably others!
Examples of queries and their expected responses:
Querying for dates
Fetching data on this file: https://commons.wikimedia.org/wiki/File:A591_road,_Lake_District_-_June_2009_Edit_1.jpg
Query:
{
"ids": ["M9832159"],
"properties": [
{"id": "P571"}
]
}Response:
{
"meta": [...]
"rows": {
"M9832159": {
"P571": [{"date":"2009-06-23"}]
}
}Querying for strings (such as external-ids)
Fetching data on this file: https://commons.wikimedia.org/wiki/File:Cat_figurine_MET_30.8.104_EGDP014435.jpg
Query:
{
"ids": ["M60928935"],
"properties": [
{"id": "P3634"}
]
}Response:
{
"meta": [...]
"rows": {
"M60928935": {
"P3634": [{"str":"572106"}]
}
}Querying for geographical coordinates
Fetching data on this file: https://commons.wikimedia.org/wiki/File:A591_road,_Lake_District_-_June_2009_Edit_1.jpg
Query:
{
"ids": ["M9832159"],
"properties": [
{"id": "P1259"}
]
}Response:
{
"meta": [...]
"rows": {
"M9832159": {
"P1259": [{"str":"54.43941,-2.972027"}]
}
}@Spinster would you have an example of a property with a "Quantity" datatype being used as main statement (not qualifier) on Commons?