Question

我有这个用户在运行时输入的查询。

SELECT * FROM Reports 
WHERE ReportDate > DATEADD(d, @Days, getdate())
AND ReportCode = cast(@Reportcode as int)

C＃.Net或SQL中是否有任何方法可以从此sql查询中检索参数名称 @Days 和 @ReportCode ？

使用@字符的正则表达式或字符串匹配不是完全证明，因为参数名称可能以空格结尾，也可能不以空格结尾。它们可以紧跟逗号或括号等，名称本身可以包含特殊字符。

如果我在不提供参数值的情况下执行此查询，则sql引擎会抛出异常必须声明标量变量＆＃34; @ Days＆＃34; 。我可以捕获异常并获取第一个参数名称，但是在查询中获取下一个参数会非常复杂。

Answer 1

exec sp_describe_undeclared_parameters N'SELECT * FROM Reports 
WHERE ReportDate > DATEADD(d, @Days, getdate())
AND ReportCode = cast(@Reportcode as int)'

输出：

parameter_ordinal name          suggested_system_type_id suggested_system_type_name  
----------------- ------------- ------------------------ ----------------------------
1                 @Days         56                       int                         
2                 @Reportcode   56                       int

（跳过更多列）

但是，这是SQL Server功能，而不是ADO.NET功能。

如果我在不提供参数值的情况下执行此查询，

这里的关键技巧非常简单： 提供正确的参数

注意：您还可以使用@params告诉您已经了解的。有关详细信息，请see the documentation。

Answer 2

create table login_db(UserName varchar(50),Password varchar(50))

go
create proc sp_logininsertdb
(@UserName varchar(50),@Password varchar(50))
as
begin
insert into login_db values(@UserName,@Password)
end

drop proc sp_logininsertdb 

exec   sp_logininsertdb @UserName='admin',@Password='admin'


go
create proc sp_loginviewdb
as
select *from login_db

exec sp_loginview_db



create table addemployee_db(id int identity(1,1),employeename varchar(50),dob Date,location varchar(50),gender varchar(50),doj Date,experience int,ctc int,designation varchar(50),unithead varchar(50),projectid int)


go
create procedure sp_addemployeedb(@id int out,@employeename varchar(50),@dob Date,@location varchar(50),@gender varchar(50),@doj Date,@experience int,@ctc int,@designation varchar(50),@unithead varchar(50),@projectid int)
as
begin 
insert into addemployee_db values (@employeename,@dob,@location,@gender,@doj,@experience,@ctc,@designation,@unithead,@projectid)
set @id=@@IDENTITY
end

declare @result int

exec sp_addemployee @id=@result output,@employeename='lokesh',
@dob='03/16/1994',@location='tvm',@gender='male',@doj='01/18/2016',
@experience=1,@ctc=4,@designation='ASE',@unithead='head1',@projectid='001'
print @result


go
create proc sp_viewemployee_db
as
begin
select * from addemployee_db
end


exec sp_viewemployee_db

drop proc sp_updateemployee_db

drop proc sp_editemployee_db



go
create procedure sp_editemployee_db(@id int,@employeename varchar(50),@dob Date,@location varchar(50),@gender varchar(50),@doj Date,@experience int,@ctc int,@designation varchar(50),@unithead varchar(50),@projectid int)
as
begin
update addemployee_db set employeename=@employeename,dob=@dob,location=@location,gender=@gender,doj=@doj,experience=@experience,ctc=@ctc,designation=@designation,unithead=@unithead,projectid=@projectid
where id=@id
end

exec sp_editemployee_db @id=10,@employeename='avaneesh',
@dob='10/11/1992',@location='Trivandrum',@gender='male',@doj='01/18/2016',
@experience=2,@ctc=7,@designation='ASET',@unithead='head2',@projectid='002'



go
create proc sp_updateemployee_db
as
begin
select * from addemployee_db
exec sp_updateemployee_db
end


drop proc sp_deletemployee_db


go
create proc sp_deletemployee_db
(@id int out)
as
begin
delete from addemployee_db where id=@id
end

exec sp_deletemployee @id=12


go
create proc sp_deleteemployee_db
as
begin
select * from addemployee_db
exec sp_deleteemployee_db
end

exec sp1_login_db




create table databinding_db(location varchar(20))


go
create proc sp_databindinginsertdb
(
@location varchar(20)
)
as
begin
insert into databinding_db
values(@location)
end






drop table databinding_db

drop proc sp_databindinginsertdb

select * from databinding_db


exec sp_databindinginsertdb 'chennai'
exec sp_databindinginsertdb 'trivandrum'
exec sp_databindinginsertdb 'puducherry'
exec sp_databindinginsertdb 'trichy'

select * from databinding_db



go
create proc sp_databindingdb
as
begin
select * from databinding_db
end

如何使用C＃Ado.Net在sql查询中查找参数

2 个答案: