some examples.js

johny@johny-X51RL:~$ mongo
"MongoDB shell version: 1.6.3"
"Thu Sep 22 21:28:06 *** warning: spider monkey build without utf8 support.  consider rebuilding with utf8 support"
"connecting to: test"
 var student = {name:'Alex',surname:'Astrouski', age:'20', courses:['math','databases','physics']}
 var student2 = {name:'Some',surname:'Body', age:'200', courses:['math','databases','physics']}
 var student3 = {name:'Hare',surname:'Krishna', age:'600', courses:['math','databases','physics']}
"Создал пару студентов (документов), теперь записываю в коллекцию:"
 db.students.save(student)
 db.students.save(student2)
 db.students.save(student3)
"Какие у меня вообще есть коллекции?"
 show collections
students
system.indexes

"А найду-ка я всех студентов (analog SELECT * FROM STUDENTS):"
 db.students.find()

{ "_id" : ObjectId("4e7b709bde6358919e483634"), "name" : "Alex", "surname" : "Astrouski", "age" : "20", "courses" : [ "math", "databases", "physics" ] }
{ "_id" : ObjectId("4e7b709fde6358919e483635"), "name" : "Some", "surname" : "Body", "age" : "200", "courses" : [ "math", "databases", "physics" ] }
{ "_id" : ObjectId("4e7b70a1de6358919e483636"), "name" : "Hare", "surname" : "Krishna", "age" : "600", "courses" : [ "math", "databases", "physics" ] }

"Всех кроме саш:"

> db.students.find({name : {$ne : "Alex"}}) 

{ "_id" : ObjectId("4e7b709fde6358919e483635"), "name" : "Some", "surname" : "Body", "age" : "200", "courses" : [ "math", "databases", "physics" ] }
{ "_id" : ObjectId("4e7b70a1de6358919e483636"), "name" : "Hare", "surname" : "Krishna", "age" : "600", "courses" : [ "math", "databases", "physics" ] }

"Числа записываются, кстати без кавычек -- добавлю еще одну запись:"

> db.students.save({name:'Somebodywithoutsurname', age:600, courses:['math','databases','physics']})

"Сначала выберу тех у кого есть поле 'фамилия' потом тех у кого нет его."

> db.students.find({surname : { $exists : true } } )
{ "_id" : ObjectId("4e7b709bde6358919e483634"), "name" : "Alex", "surname" : "Astrouski", "age" : "20", "courses" : [ "math", "databases", "physics" ] }
{ "_id" : ObjectId("4e7b709fde6358919e483635"), "name" : "Some", "surname" : "Body", "age" : "200", "courses" : [ "math", "databases", "physics" ] }
{ "_id" : ObjectId("4e7b70a1de6358919e483636"), "name" : "Hare", "surname" : "Krishna", "age" : "600", "courses" : [ "math", "databases", "physics" ] }
> db.students.find({surname : { $exists : false } } )
{ "_id" : ObjectId("4e7b751abe26c83a1b6cadd0"), "name" : "Somebodywithoutsurname", "age" : 600, "courses" : [ "math", "databases", "physics" ] }