1、讀取數據庫連接
private SqlSugarClient GetInstance()
{
string conmstring = System.Web.Configuration.WebConfigurationManager.ConnectionStrings["BaseDb"].ToString();
SqlSugarClient db = new SqlSugarClient(new ConnectionConfig() { InitKeyType = InitKeyType.Attribute, ConnectionString = conmstring, DbType = SqlSugar.DbType.SqlServer, IsAutoCloseConnection = true });
return db;
}
2、定義別名
[SugarTable("ado.Student")] //別名處理
public
class
Student {
[SugarColumn(IsIgnore=
true
)]
public
string
xxx{
get
;
set
;}
//這列在ORM會過濾掉
[SugarColumn(ColumnName=
"name"
)]
public
string
xxx{
get
;
set
;}
//這列在ORM會當成 name處理
}
我們可以用Add的方式
db.MappingTables.Add()
db.MappingColumns.Add() db.IgnoreColumns.Add()
我們還可以用AS
//別名表
db.Queryable<T>().As("tableName").ToList();
//別名列
.Where(it=>SqlFunc.MappingColumn(it.OldName,"NewName") == "jack")
他們之間的優先級：
AS>Add>屬性方式
3、小技巧
Queryable<T>().AS("(select * from [student]) t").ToPageList(1,2);
使用函數 SqlFunc類
var
getByFuns = db.Queryable<Student>().Where(it => SqlFunc.IsNullOrEmpty(it.Name)).ToList();
|
是否存在這條記錄
var isAny2 = db.Queryable<Student>().Any(it => it.Id == -1);
獲取同一天的記錄
var getTodayList = db.Queryable<Student>().Where(it => SqlFunc.DateIsSame(it.CreateTime, DateTime.Now)).ToList();
4、IN查詢
var in1 = db.Queryable<Student>().In(it=>it.Id,new int[] { 1, 2, 3 }).ToList();
var in1 = db.Queryable<Student>().In(it=>it.Id,new int[] { 1, 2, 3 }).ToList();
5、多個Queryable
var q1= db.Queryable<DataItemEntity, DataItemDetailEntity>((a, b) => new object[] {
JoinType.Left,a.ItemId==b.ItemId,
}).Select((a,b) => b);
var q2 = db.Queryable<QRFileEntity>();
var innerjoin = db.Queryable(q1, q2, JoinType.Inner, (j1, j2) => j1.ItemDetailId == j2.ParentId).Select((j1, j2) => j1).ToList();
6、MappingColumn 實現復雜的功能
var s2 = db.Queryable<Student>()
.Select(it =>
new
{ id = it.Id, rowIndex=SqlFunc.MappingColumn(it.Id,
" row_number() over(order by id)"
) }).ToList();
var propertyName = "ItemDetailId'"; //類中的屬性的名稱
var dbColumnName = db.EntityProvider.GetDbColumnName<DataItemDetailEntity>(propertyName);
var list2 = db.Ado.SqlQuery<DataItemDetailEntity>(string.Format("select * from DataItemDetail where {0} =@value ", dbColumnName), new { value =""}).ToList();
8、分組返回所有列
var file = db.Queryable<QRFileEntity>().PartitionBy(c => c.FName).Select(c => c).ToList();
9、聯表更新
var res = db.Updateable<QRFileEntity>().UpdateColumns(c => new QRFileEntity
{
CreateUserName = SqlFunc.Subqueryable<UserEntity>().Where(d => d.UserId == "").Select(d => d.RealName),
FName = ""
}).Where(c => c.FileId == "").ExecuteCommand();