一.准备阶段
1.查询数据清单准备
2.这里先将SQL语句执行顺序列出来,方便后面语句对比更好理解
(8)SELECT (9)DISTINCT (11)<Top Num> <select list> (1)FROM [left_table] (3)<join_type> JOIN <right_table> (2) ON <join_condition> (4)WHERE <where_condition> (5)GROUP BY <group_by_list> (6)WITH <CUBE | RollUP> (7)HAVING <having_condition> (10)ORDER BY <order_by_list>
二.查询全表
1. SQL:
select * from ppeflow
2. MongoDB NO SQL:
db.ppeflow.find()
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库 FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤 FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空 var resultList = ppeflows.Find(filter).ToList();//获取集合
三.查询数据总数
1. SQL:
select count(1) from ppeflow
2. MongoDB NO SQL:
db.ppeflow.find({}).count()
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空
var result = ppeflows.CountDocuments(filter); //获得集合数量
四.查询并排序
1. SQL:
select * from ppeflow order by orderid
select *from ppeflow order by orderid desc
2. MongoDB NO SQL:
db.ppeflow.find().sort({'orderid':1})
db.ppeflow.find().sort({'orderid':-1})
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空
var builderSort = Builders<ppeflow>.Sort.Ascending(t => t.orderid); //创建排序
var resultList = ppeflows.Find(filter).Sort(builderSort).ToList();//获取集合
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过
FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空
var resultList = ppeflows.Find(filter).SortByDescending(t => t.orderid).ToList();//获取集合
五.查询TOP前10条记录
1. SQL:
select top 10 * from ppeflow
2. MongoDB NO SQL:
db.ppeflow.find().limit(10)
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空
var resultList = ppeflows.Find(filter).Limit(10).ToList();//获取集合
六.查询从第6条到第10条记录(即:跳过前5条记录起的后5条记录)
1. SQL:
select * from ppeflow limit 5,5
2. MongoDB NO SQL:
db.ppeflow.find().skip(5).limit(5)
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空
var resultList = ppeflows.Find(filter).Skip(5).Limit(5).ToList();//获取集合
七.查询distinct去除重复字段
1. SQL:
select DISTINCT techname from ppeflow
2. MongoDB NO SQL:
db.ppeflow.distinct('techname')
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
FilterDefinition<ppeflow> filter = builderFilter.Empty;//过滤为空
var resultList = ppeflows.Distinct(tt => tt.techname, filter).ToList();//获取集合
八.查询Group by分组
1. SQL:
select techname,count(1) as total from ppeflow group by techname
2. MongoDB NO SQL:
db.ppeflow.group({
key:{ "techname":true}
,initial: {techname:'',total: 0}
,reduce: function(doc, out)
{
out.techname = doc.techname;
out.total += doc.orderid;
}
})
3. MongoDB C#
//待完善
九.查询条件>,>=,<,<=
1. SQL:
select techname from ppeflow where orderid > 10
select techname from ppeflow where orderid >= 10
select techname from ppeflow where orderid < 10
select techname from ppeflow where orderid <= 10
2. MongoDB NO SQL:
db.ppeflow.find({'orderid':{$gt:10}})
db.ppeflow.find({'orderid':{$gte:10}})
db.ppeflow.find({'orderid':{$lt:10}})
db.ppeflow.find({'orderid':{$lte:10}})
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
FilterDefinition<ppeflow> filter = builderFilter.Where(t => t.orderid > 10); ;//过滤条件 改为对应的>=,<,<=
var resultList = ppeflows.Find(filter).ToList();//获取集合
十.查询条件in等于其实中任意一个
1. SQL:
select techname from ppeflow where orderid in (10,11,12)
2. MongoDB NO SQL:
db.ppeflow.find({'orderid':{$in:[10,11,12]}})
3. MongoDB C#
IMongoCollection<ppeflow> ppeflows = db.GetCollection<ppeflow>("ppeflow");//指定数据库
FilterDefinitionBuilder<ppeflow> builderFilter = Builders<ppeflow>.Filter; //创建过滤
var list1 = new List<int> { 10, 11, 12 };
var filter = builderFilter.Where(tt => list1.IndexOf(tt.orderid)>-1); //in 条件
var resultList = ppeflows.Find(filter).ToList();//获取集合