如何在C++中构建mongo$in查询
How to build a mongo $in query in C++
我想知道如何在C++中构建$in查询。我能够成功地构建一个$nin查询,如下所示:
mongo::BSONArrayBuilder bab;
bab << "category1";
bab << "category2";
mongo::BSONObjBuilder bobQuery;
bobQuery << "category" << mongo::NIN << bab.arr();
但是,似乎没有相应的mongo::IN来构建相应的$IN查询。至少,我找不到一个挖掘源头的人。
您可以这样做:
mongo::BSONObjBuilder bobQuery;
bobQuery << "category" << BSON( "$in" << bab.arr());
或
mongo::BSONObjBuilder bobQuery;
mongo::BSONObjBuilder catQuery;
bobQuery.append("$in", bab.arr());
catQuery.append("category", bobQuery.done());
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- 如何在C++中构建mongo$in查询