}}
== Basics ==
In UBIK, id marker scan queries are used for fetching a list of [[Contentclass|ContentClasses]] identified by scan code codes ([http://dev.metaio.com/sdk/tracking-config/optical-tracking/id-marker/ id markerID Marker], [http://en.wikipedia.org/wiki/Barcode barcodeBarcode], [http://en.wikipedia.org/wiki/QRcode qr codeQR Code]) from the database. All of these objects have to fullfill the classification [[SYSCLS_OBJECTWITHIDMARKER]] in order to be found as the query result. The id marker scan query itself inherits functionality from [[Query|Query]] and has the classification interface [[SYSCLS_IDMARKERSCANQUERY]].
Id marker scan queries can be used in different scenarios with objects identified by scan codes:
* data fetching (n records)
{{Attention|When selecting the query root node, please consider that possibly a huge amount of derived MetaClasses must be recusively checked for implementing the classification interface! Using a FilterClass that directly implements the interface reduces the processing time to a minimum!}}
==Filter Criteria==
The filter criteria of an IdMarkerScanQuery basically consists of an ID Marker, a Barcode or a QR Code. If these code search criteria are logically combined with "AND" if provided together (e.g. QR Code AND Barcode). On the other hand providing only one of these scan code values, the content is matched to the specified code type (e.g. Barcode) only.
[[Category:System MetaClasses]]
[[Category:Queries]]