获取所有MongoDB文档，但不获取具有两个给定条件的文档？
在以下任何一种情况下，获取具有某些给定条件的所有MongoDB文档
情况1以下是使用$ne运算符查询没有单个条件的所有文档的查询
db.yourCollectionName.find({yourFieldName:{$ne:"yourValue"}}).pretty();情况2以下是使用$nin运算符查询所有没有两个给定条件的文档的查询
db.yourCollectionName.find({yourFieldName:{$nin:["yourValue1","yourValue2"]}}).pretty();让我们首先创建一个集合。以下是使用文档创建集合的查询
>db.findAllExceptFromOneOrtwoDemo.insertOne({"StudentName":"Larry","StudentSubjectName":"Java"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c993d82330fd0aa0d2fe4d2")
}
>db.findAllExceptFromOneOrtwoDemo.insertOne({"StudentName":"Chris","StudentSubjectName":"C++"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c993d8f330fd0aa0d2fe4d3")
}
>db.findAllExceptFromOneOrtwoDemo.insertOne({"StudentName":"Robert","StudentSubjectName":"C"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c993d99330fd0aa0d2fe4d4")
}
>db.findAllExceptFromOneOrtwoDemo.insertOne({"StudentName":"David","StudentSubjectName":"Python"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c993da4330fd0aa0d2fe4d5")
}以下是在find()方法的帮助下显示集合中所有文档的查询
> db.findAllExceptFromOneOrtwoDemo.find().pretty();
这将产生以下输出
{
"_id" : ObjectId("5c993d82330fd0aa0d2fe4d2"),
"StudentName" : "Larry",
"StudentSubjectName" : "Java"
}
{
"_id" : ObjectId("5c993d8f330fd0aa0d2fe4d3"),
"StudentName" : "Chris",
"StudentSubjectName" : "C++"
}
{
"_id" : ObjectId("5c993d99330fd0aa0d2fe4d4"),
"StudentName" : "Robert",
"StudentSubjectName" : "C"
}
{
"_id" : ObjectId("5c993da4330fd0aa0d2fe4d5"),
"StudentName" : "David",
"StudentSubjectName" : "Python"
}案例1单一条件
以下是查询
> db.findAllExceptFromOneOrtwoDemo.find({StudentSubjectName:{$ne:"C"}}).pretty();这将产生以下输出
{
"_id" : ObjectId("5c993d82330fd0aa0d2fe4d2"),
"StudentName" : "Larry",
"StudentSubjectName" : "Java"
}
{
"_id" : ObjectId("5c993d8f330fd0aa0d2fe4d3"),
"StudentName" : "Chris",
"StudentSubjectName" : "C++"
}
{
"_id" : ObjectId("5c993da4330fd0aa0d2fe4d5"),
"StudentName" : "David",
"StudentSubjectName" : "Python"
}案例2两个条件
以下是查询
>db.findAllExceptFromOneOrtwoDemo.find({StudentSubjectName:{$nin:["C++","Python"]}}).pretty();这将产生以下输出
{
"_id" : ObjectId("5c993d82330fd0aa0d2fe4d2"),
"StudentName" : "Larry",
"StudentSubjectName" : "Java"
}
{
"_id" : ObjectId("5c993d99330fd0aa0d2fe4d4"),
"StudentName" : "Robert",
"StudentSubjectName" : "C"
}