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help db.help(); db.yourcoll.help();
use raykaeso;
当创建一个集合(table)的时候会自动创建当前数据库
show dbs;
db.dropdatabase();
db.clonedatabase(“127.0.0.1”);
将指定机器上的数据库的数据克隆到当前数据库
db.copydatabase(“mydb”, “temp”, “127.0.0.1”);
将本机的mydb的数据复制到temp数据库中
db.repairdatabase();
db.getname()/db;
db.stats();
db.version();
db.getmongo();
db.getpreverror(); db.reseterror();
db.createcollection(“collname”, {size: 20, capped: 5, max: 100});//创建成功会显示{“ok”:1} //判断集合是否为定容量db.collname.iscapped();
db.getcollection(“account”);
db.getcollectionnames();
db.printcollectionstats();
db.yourcoll.count();
db.yourcoll.datasize();
db.yourcoll.getdb();
db.coll.stats();
db.coll.totalsize();
db.coll.storagesize();
db.coll.renamecollection(“ray”);
将coll重命名为ray
db.coll.drop();
db.createuser({user: 'username', pwd: 'xxxx', roles: [{role: 'readwrite', db: 'dbname'}]});
添加用户、设置密码、是否只读
db.auth(“ray”, “123456”);
show users;
db.removeuser(“username”);
db.userinfo.find();
相当于:select* from userinfo;
默认每页显示20条记录,当显示不下的情况下,可以用it迭代命令查询下一页数据。注意:键入it命令不能带“;”
但是你可以设置每页显示数据的大小,用dbquery.shellbatchsize= 50;这样每页就显示50条记录了。
db.userinfo.distinct(“name”);
会过滤掉name中的相同数据
相当于:select distict name from userinfo;
db.userinfo.find({“age”: 22});
相当于: select * from userinfo where age = 22;
mongodb中条件操作符有:
(>) 大于 – $gt
(<) 小于 – $lt (>=) 大于等于 – $gte
(<= ) 小于等于 – $lte
db.userinfo.find({age: {$gt: 22}}); 相当于:select * from userinfo where age>22; db.userinfo.find({age: {$lt: 22}}); 相当于:select * from userinfo where age<22; db.userinfo.find({age: {$gte: 25}}); 相当于:select * from userinfo where age >= 25;
db.userinfo.find({name: /mongo/}); //相当于%% select * from userinfo where name like ‘%mongo%';
db.userinfo.find({}, {name: 1, age: 1}); 相当于:select name, age from userinfo;
当然name也可以用true或false
db.userinfo.find({age: {$gt: 25}}, {name: 1, age: 1}); 相当于:select name, age from userinfo where age <25;
升序:db.userinfo.find().sort({age: 1});
降序:db.userinfo.find().sort({age: -1});
db.userinfo.find().limit(5); 相当于:select * from userinfo limit 5;
db.userinfo.find().skip(10); 相当于:select count() from userinfo as total; select from userinfo limit 10,total;
db.userinfo.find().limit(10).skip(5);
可用于分页,limit是pagesize,skip是第几页pagesize
相当于:select from userinfo limit 5,10;
db.userinfo.find({$or: [{age: 22}, {age: 25}]}); 相当于:select * from userinfo where age = 22 or age = 25;
db.userinfo.findone(); db.userinfo.find().limit(1); 相当于:select * from userinfo limit 1;
db.userinfo.find({age: {$gte: 25}}).count(); 相当于:select count(*) from userinfo where age >= 20;
db.userinfo.ensureindex({name: 1}); db.userinfo.ensureindex({name: 1, ts: -1});
db.userinfo.getindexes();
db.userinfo.totalindexsize();
db.users.reindex();
db.users.dropindex(“name_1″);
db.users.dropindexes();
db.users.save({name: ‘zhangsan', age: 25, sex: true});
添加的数据的数据列,没有固定,根据添加的数据为准
db.users.update({age: 25}, {$set: {name: ‘changename'}}, false, true); 相当于:update users set name = ‘changename' where age = 25; db.users.update({name: ‘lisi'}, {$inc: {age: 50}}, false, true); 相当于:update users set age = age + 50 where name = ‘lisi'; db.users.update({name: ‘lisi'}, {$inc: {age: 50}, $set: {name: ‘hoho'}}, false, true); 相当于:update users set age = age + 50, name = ‘hoho' where name = ‘lisi';
db.users.remove({age: 132});
db.users.findandmodify({ query: {age: {$gte: 25}}, sort: {age: -1}, update: {$set: {name: ‘a2′}, $inc: {age: 2}}, remove: true });
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