【MongoDB学习笔记15】MongoDB的查询：find查询条件

find除了精确查询外，可以匹配更多的条件；

一、比较操作符

$lt代表<;

$lte代表<=;

$gt代表>;

$gte代表>=;

> db.post.find()   { "_id" : ObjectId("54a530c3ff0df3732bac1681"), "id" : 2, "name" : "joe", "age" : 30, "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a530c3ff0df3732bac1680"), "id" : 1, "name" : "joe", "age" : 30, "comments" : [ "test2", "test9", "test5" ], "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a9700e1b5afd45354fd086"), "id" : 3, "test3" : 3 }    { "_id" : ObjectId("54a9701c1b5afd45354fd087"), "id" : 4, "test4" : 4 }    { "_id" : ObjectId("54a970281b5afd45354fd088"), "id" : 5, "test5" : 5 }    { "_id" : ObjectId("54a970351b5afd45354fd089"), "id" : 6, "test6" : 6 }    { "_id" : ObjectId("54a970781b5afd45354fd08a"), "id" : 7, "test7" : 7 }    { "_id" : ObjectId("54a970831b5afd45354fd08b"), "id" : 8, "test8" : 8 }    { "_id" : ObjectId("54a970901b5afd45354fd08c"), "id" : 9, "test9" : 9 }    { "_id" : ObjectId("54a9709c1b5afd45354fd08d"), "id" : 10, "test10" : 10 }    > db.post.find({"id":{"$gte":5,"$lte":7}})    { "_id" : ObjectId("54a970281b5afd45354fd088"), "id" : 5, "test5" : 5 }    { "_id" : ObjectId("54a970351b5afd45354fd089"), "id" : 6, "test6" : 6 }    { "_id" : ObjectId("54a970781b5afd45354fd08a"), "id" : 7, "test7" : 7 }    >

$ne代表不等于:

> db.post.find({"id":{"$ne":8}})   { "_id" : ObjectId("54a530c3ff0df3732bac1681"), "id" : 2, "name" : "joe", "age" : 30, "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a530c3ff0df3732bac1680"), "id" : 1, "name" : "joe", "age" : 30, "comments" : [ "test2", "test9", "test5" ], "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a9700e1b5afd45354fd086"), "id" : 3, "test3" : 3 }    { "_id" : ObjectId("54a9701c1b5afd45354fd087"), "id" : 4, "test4" : 4 }    { "_id" : ObjectId("54a970281b5afd45354fd088"), "id" : 5, "test5" : 5 }    { "_id" : ObjectId("54a970351b5afd45354fd089"), "id" : 6, "test6" : 6 }    { "_id" : ObjectId("54a970781b5afd45354fd08a"), "id" : 7, "test7" : 7 }    { "_id" : ObjectId("54a970901b5afd45354fd08c"), "id" : 9, "test9" : 9 }    { "_id" : ObjectId("54a9709c1b5afd45354fd08d"), "id" : 10, "test10" : 10 }    >

$in可以查询多个键值:

> db.post.find({"id":{"$in":[4,2,8]}})   { "_id" : ObjectId("54a530c3ff0df3732bac1681"), "id" : 2, "name" : "joe", "age" : 30, "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a9701c1b5afd45354fd087"), "id" : 4, "test4" : 4 }    { "_id" : ObjectId("54a970831b5afd45354fd08b"), "id" : 8, "test8" : 8 }    >

$nin用法：

> db.post.find({"id":{"$nin":[4,2,8]}})   { "_id" : ObjectId("54a530c3ff0df3732bac1680"), "id" : 1, "name" : "joe", "age" : 30, "comments" : [ "test2", "test9", "test5" ], "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a9700e1b5afd45354fd086"), "id" : 3, "test3" : 3 }    { "_id" : ObjectId("54a970281b5afd45354fd088"), "id" : 5, "test5" : 5 }    { "_id" : ObjectId("54a970351b5afd45354fd089"), "id" : 6, "test6" : 6 }    { "_id" : ObjectId("54a970781b5afd45354fd08a"), "id" : 7, "test7" : 7 }    { "_id" : ObjectId("54a970901b5afd45354fd08c"), "id" : 9, "test9" : 9 }    { "_id" : ObjectId("54a9709c1b5afd45354fd08d"), "id" : 10, "test10" : 10 }    >

$or的用法：

> db.post.find({"$or":[{"sex":1},{"id":5}]})   { "_id" : ObjectId("54a530c3ff0df3732bac1681"), "id" : 2, "name" : "joe", "age" : 30, "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a530c3ff0df3732bac1680"), "id" : 1, "name" : "joe", "age" : 30, "comments" : [ "test2", "test9", "test5" ], "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a970281b5afd45354fd088"), "id" : 5, "test5" : 5 }    >

$mod会将查询的值除以第一个给定的值，若余数匹配第二个值，则匹配成功；

> db.post.find()   { "_id" : ObjectId("54a530c3ff0df3732bac1681"), "id" : 2, "name" : "joe", "age" : 30, "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a530c3ff0df3732bac1680"), "id" : 1, "name" : "joe", "age" : 30, "comments" : [ "test2", "test9", "test5" ], "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a9700e1b5afd45354fd086"), "id" : 3, "test3" : 3 }    { "_id" : ObjectId("54a9701c1b5afd45354fd087"), "id" : 4, "test4" : 4 }    { "_id" : ObjectId("54a970281b5afd45354fd088"), "id" : 5, "test5" : 5 }    { "_id" : ObjectId("54a970351b5afd45354fd089"), "id" : 6, "test6" : 6 }    { "_id" : ObjectId("54a970781b5afd45354fd08a"), "id" : 7, "test7" : 7 }    { "_id" : ObjectId("54a970831b5afd45354fd08b"), "id" : 8, "test8" : 8 }    { "_id" : ObjectId("54a970901b5afd45354fd08c"), "id" : 9, "test9" : 9 }    { "_id" : ObjectId("54a9709c1b5afd45354fd08d"), "id" : 10, "test10" : 10 }    { "_id" : ObjectId("54aa8a90652d8bdfa0566d34"), "id" : 11, "test10" : 11 }    > db.post.find({"id":{$mod:[5,1]}})    { "_id" : ObjectId("54a530c3ff0df3732bac1680"), "id" : 1, "name" : "joe", "age" : 30, "comments" : [ "test2", "test9", "test5" ], "sex" : 1, "school" : "marry" }    { "_id" : ObjectId("54a970351b5afd45354fd089"), "id" : 6, "test6" : 6 }    { "_id" : ObjectId("54aa8a90652d8bdfa0566d34"), "id" : 11, "test10" : 11 }    >