This function allows you to add words to a free text update batch. It can be called in sequence to feed group of documents that share a common document ID and the result is similar to the single call whose text_or_xml parameter is concatenation of documents of that group. It is even allowed to mix XML and non-XML documents by feeding an XML document and some text documents: the first document to feed may be an XML document, other documents should be only texts.
If one wishes to mix XML and non-XML documents, knowledge of details of the indexing method is needed. vt_batch_feed assigns a sequence number to every word of the provided document using an internal counter. The call of vt_batch_d_id not only sets document id but also resets this counter to 0. The first element of an XML document should have number 0 so it is impossible to feed an XML document if there were other calls of vt_batch_feed after the last vt_batch_d_id. Moreover, xcontains will ignore words from text documents that were fed after the first XML document, only contains will use all data.
None.
Please refer to examples for function vt_batch_feed_offband.