db.test.insert([
{"name":"xiaoming","age":"10"},
{"name":"xiaohong","age":"20"},
{"name":"xiaolan","age":"30"},
{"name":"xiaolv","age":"40"},
{"name":"xiaozi","age":"50"},
{"name":"xiaohei","age":"60"}
]);
db.test.find();
db.test.find({$or:[{"age":"10"},{"name":"xiaoming"}]});
db.test.createIndex({"age" : 1});
db.test.find({"age" : {$in : ["10","20"]}});
//$lte小于 $ne 不等于
db.test.find({$and : [{"age":{$ne : "10"}},{"age" :{$lte : "30"}}]});
//$exists 字段非空
db.test.find({
$and : [
{"age":{$ne : "10"}},
{"name" :{$exists : true}}
]
});
//使用$and拼接大量的 条件, 两个or之间是且的关系, 第一个返回false 后边不会执行
db.test.find(
{
$and : [
{
$or : [{ "name":"xiaoming"} , {"name":"xiaohong"}]
},
{
$or : [{ "age" : "20" },{"age" : "30"}]
}
]
}
)
转载于:https://www.cnblogs.com/yaoxublog/p/11578381.html
