MongoDB查询以在find()中实现OR运算符
让我们创建一个包含文档的集合-
> db.demo78.insertOne({"Name1":"Chris","Name2":"Mike"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e2bd99c71bf0181ecc4228f")
}
> db.demo78.insertOne({"Name1":"Bob","Name2":"Carol"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e2bd9ac71bf0181ecc42290")
}
> db.demo78.insertOne({"Name1":"David","Name2":"Sam"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e2bd9b671bf0181ecc42291")
}
> db.demo78.insertOne({"Name1":"Jace","Name2":"John"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e2bd9bf71bf0181ecc42292")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo78.find();
这将产生以下输出-
{ "_id" : ObjectId("5e2bd99c71bf0181ecc4228f"), "Name1" : "Chris", "Name2" : "Mike" }
{ "_id" : ObjectId("5e2bd9ac71bf0181ecc42290"), "Name1" : "Bob", "Name2" : "Carol" }
{ "_id" : ObjectId("5e2bd9b671bf0181ecc42291"), "Name1" : "David", "Name2" : "Sam" }
{ "_id" : ObjectId("5e2bd9bf71bf0181ecc42292"), "Name1" : "Jace", "Name2" : "John" }以下是在find()-中实现OR运算符的查询：
> db.demo78.find({$or: [{"Name1": "Bob"}, {Name2: "John"}] });这将产生以下输出-
{ "_id" : ObjectId("5e2bd9ac71bf0181ecc42290"), "Name1" : "Bob", "Name2" : "Carol" }
{ "_id" : ObjectId("5e2bd9bf71bf0181ecc42292"), "Name1" : "Jace", "Name2" : "John" }