基本概念
数据库分为TRDB和NoSQL
TRDB包含Oracle（第一款）、MySQL等
NoSQL包含MongoDB、Redis等
NoSQL：是一种非关系型DMS，不需要固定的架构，可以避免joins链接，并且易于扩展。
MongoDB数据库构成：
数据库<集合<文档<字段
_id：唯一标识，主键
游标：指向查询结果集的指针
数据库：集合容器
集合：文档的分组，存在于单个数据库中
文档：集合中的记录，包含字段名称和值
字段：文档中的 （名称/值） 对
基本操作
MongoDB创建数据库:use DBname
rs:PRIMARY> use Employee
switched to db Employee
创建集合/表:insert()
rs:PRIMARY> db.Employee.insert(
... {
... "编号":1,
... "EmployeeName":"Smith"
... }
... )
WriteResult({
"nInserted" : 1 })
rs:PRIMARY>
insert()还可以插入数组
rs:PRIMARY> var myEmployee = [ {
"编号":2, "EmployeeName":"Smith2"},{
"编号":3,"EmployeeName":"Smith3"}]
rs:PRIMARY> db.Employee.insert(myEmployee)
BulkWriteResult({
"writeErrors" : [ ],
"writeConcernErrors" : [ ],
"nInserted" : 2,
"nUpserted" : 0,
"nMatched" : 0,
"nModified" : 0,
"nRemoved" : 0,
"upserted" : [ ]
})
rs:PRIMARY>
查询文档
rs:PRIMARY> db.Employee.find()
{
"_id" : ObjectId("6033295c785939f88516b7f4"), "Employeeid" : 1, "EmployeeName" : "Smith" }
{
"_id" : ObjectId("6033295c785939f88516b7f5"), "Employeeid" : 2, "EmployeeName" : "Mohan" }
{
"_id" : ObjectId("6033295c785939f88516b7f6"), "Employeeid" : 3, "EmployeeName" : "Joe" }
{
"_id" : 10, "EmployeeName" : "Smith" }
rs:PRIMARY>
条件查询
rs:PRIMARY> db.Employee.find({
EmployeeName:"Smith"}).forEach(printjson)
{
"_id" : ObjectId("6033295c785939f88516b7f4"),
"Employeeid" : 1,
"EmployeeName" : "Smith"
}
{
"_id" : 10, "EmployeeName" : "Smith" }
rs:PRIMARY> db.Employee.find({
Employeeid:{
$gt:2}}).forEach(printjson)
{
"_id" : ObjectId("6033295c785939f88516b7f6"),
"Employeeid" : 3,
"EmployeeName" : "Joe"
}
rs:PRIMARY>
查询修饰符 limit
rs:PRIMARY> db.Employee.find().limit(2).forEach(printjson)
{
"_id" : ObjectId("6033295c785939f88516b7f4"),
"Employeeid" : 1,
"EmployeeName" : "Smith"
}
{
"_id" : ObjectId("6033295c785939f88516b7f5"),
"Employeeid" : 2,
"EmployeeName" : "Mohan"
}
rs:PRIMARY>
排序查询：1为升序，-1为降序
rs:PRIMARY> db.Employee.find().sort({
Employeeid:-1}).forEach(printjson)
{
"_id" : ObjectId("6033295c785939f88516b7f6"),
"Employeeid" : 3,
"EmployeeName" : "Joe"
}
{
"_id" : ObjectId("6033295c785939f88516b7f5"),
"Employeeid" : 2,
"EmployeeName" : "Mohan"
}
{
"_id" : ObjectId("6033295c785939f88516b7f4"),
"Employeeid" : 1,
"EmployeeName" : "Smith"
}
{
"_id" : 10, "EmployeeName" : "Smith" }
rs:PRIMARY>
查询集合中文档数量count()
rs:PRIMARY> db.Employee.count()
4
rs:PRIMARY>
执行文档修改操作
删除 remove()
rs:PRIMARY> db.Employee.remove({
Employeeid:2})
WriteResult({
"nRemoved" : 1 })
rs:PRIMARY> db.Employee.find()
{
"_id" : ObjectId("6033295c785939f88516b7f4"), "Employeeid" : 1, "EmployeeName" : "Smith" }
{
"_id" : ObjectId("6033295c785939f88516b7f6"), "Employeeid" : 3, "EmployeeName" : "Joe" }
{
"_id" : 10, "EmployeeName" : "Smith" }
rs:PRIMARY>
更新单个/多个值 update()
rs:PRIMARY> db.Employee.update(
... {
"Employeeid":1},{
$set:{
"EmployeeName":"NewSmith"}})
WriteResult({
"nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
rs:PRIMARY> db.Employee.find()
{
"_id" : ObjectId("6033295c785939f88516b7f4"), "Employeeid" : 1, "EmployeeName" : "NewSmith" }
{
"_id" : ObjectId("6033295c785939f88516b7f6"), "Employeeid" : 3, "EmployeeName" : "Joe" }
{
"_id" : 10, "EmployeeName" : "Smith" }
rs:PRIMARY>
正则匹配 $regex
忽略大小写 $option:"i"