[MongoDB Learning Notes 15] MongoDB query: find query condition

Find can match more conditions than precise query.

I. comparison operator

$lt stands for =

> 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 does not mean:

> db.post.find ({"id": {"$ne": 8}}) {"_ id": ObjectId ("54a530c3ff0df3732bac1681"), "id": 2, "name": "joe", "age": 30, "sex": 1, "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 can query multiple key values:

> db.post.find ({"id": {"$in": [4je 2je 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 usage:

> db.post.find ({"id": {"$nin": [4je 2je 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} >

Usage of $or:

> 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 divides the value of the query by the first given value. If the remainder matches the second value, the match is successful.

> 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: [5jue 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} >