[英]How to find parameters in sql query using C# Ado.Net
I have got this query which is entered by user at run time.我得到了用户在运行时输入的这个查询。
SELECT * FROM Reports
WHERE ReportDate > DATEADD(d, @Days, getdate())
AND ReportCode = cast(@Reportcode as int)
Is there any way in C# .Net or SQL to retrieve the parameter names @Days and @ReportCode from this sql query? 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 ?
Regex or string matching using @ character is not full proof as parameter names may or may not end with a space.使用@ 字符进行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。 They can be immediately followed by a comma or parenthesis etc. and the name itself can contain a special character.
它们可以紧跟逗号或括号等,并且名称本身可以包含特殊字符。
If I execute this query without providing parameter values, the sql engine throws exception Must declare the scalar variable "@Days" .如果我在不提供参数值的情况下执行此查询,sql 引擎将抛出异常Must declare the scalar variable "@Days" 。 I can catch the exception and get first parameter name, but then it would be very complex to get next parameter in query.
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将非常复杂。
exec sp_describe_undeclared_parameters N'SELECT * FROM Reports
WHERE ReportDate > DATEADD(d, @Days, getdate())
AND ReportCode = cast(@Reportcode as int)'
outputs:输出:
parameter_ordinal name suggested_system_type_id suggested_system_type_name
----------------- ------------- ------------------------ ----------------------------
1 @Days 56 int
2 @Reportcode 56 int
(lots more columns skipped) (跳过了更多的列)
However, this is a SQL Server feature, not an ADO.NET one.但是,这是一项 SQL Server 功能,而不是 ADO.NET 功能。
If I execute this query without providing parameter values,
如果我在不提供参数值的情况下执行此查询,
The key trick here is remarkably simple: supply the correct parameters这里的关键技巧非常简单:提供正确的参数
Note: you can also use @params
to tell it about the ones you already know about .注意:你也可以使用
@params
告诉它你已经知道的那些。 For more details, see the documentation .有关更多详细信息,请参阅文档。
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
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