mongodb常用语句(查询)
mongodb常用语句(查询)
查询所有数据
db.songs.find();
www.zzzyk.com
查第一条
db.songs.findOne();
去重某列(分组)
db.songs.distinct("id");
等值查询
db.songs.find({"id":1});
非等值查询
db.songs.find({"id":{$gt:1}});
db.songs.find({"id":{$lt:2}});
db.songs.find({"id":{$gte:1}});
db.songs.find({"id":{$lte:2}});
db.songs.find({"id":{$lte:4,$gte:3}});
包含查询 www.zzzyk.com
db.songs.find({"name":/a/});(包含a)
db.songs.find({"name":/^a/});(以a开头)
查询结果指定列
db.songs.find({},{name:1}); (只显示name列)
db.songs.find({},{name:1,id:1}); (显示name和id两列)
排序(1:asc,-1:desc)
db.songs.find().sort({id:1});
db.songs.find().sort({id:-1});
db.songs.find().sort({"id":1,"name":-1});
分页 limit是pageSize，skip是第几页*pageSize
db.songs.find().sort({"id":-1}).limit(1);
db.songs.find().sort({"id":-1}).skip(1).limit(1);
OR查询
db.songs.find({$or:[{"id":1},{"id":2}]})
db.songs.find({$or:[{"id":1},{"id":{$gte:3}}]})
<>
db.songs.find({"name":{"$ne":"kebi"}});
in
db.songs.find({"age":{$in:[12,22,33]}});
选择特定列(0=false,!0=true)
db.songs.find({"age":{$in:[12,22,33]}},{age:0});
db.songs.find({"age":{$in:[12,22,33]}},{age:1});
