How to use an SSIS Variable Value or Project Parameter Value as an expression body and then evaluate it to another Variable

Question

I have an SSIS Project (Visual studio 2019 - Project Deployment Model) which contains 100 SSIS Packages.

The name structure of each package is TableName _Table.dtsx ( For example: If my table name is Employees then the package name will be: Employees_Table.dtsx ).

Every SSIS package has 2 variables

@[User::TableName]

@[User::TableColumn]

which have hardcoded values,

and a variable that uses above variables values to create a query (Expression Evaluation)

@[User::Logging_sql_statement] = 

    "Insert into dbo.Log_Table (table_name,delta_column_name,start_time) 
    values ('" + @[User::TableName] + "','"+ @[User::TableColumn] + "','"+ (DT_WSTR, 50) (DT_DBTIMESTAMP) @[System::StartTime] + "')"

My problem is the following: Recently we made some changes in the SSIS logging mechanism that we used, so I had to go to every SSIS package of 100 SSIS packages and modify the Expression at @[User::Logging_sql_statement] Variable.

So in order to avoid having to modify 100 SSIS in the future if new change occurs I wondered if there was a way I could save the expression body to a project parameter and then evaluate its value as an expression to @[User::Logging_sql_statement] variable in every SSIS Package.

In the above scenario, I would only have to modify the value of the parameter in the future.

So i created a Project Parameter and set its value hardcoded like this:

@[$Project::Parameter] = 
"Insert into dbo.Log_Table (table_name,delta_column_name,start_time) 
values ('" + @[User::TableName] + "','"+ @[User::TableColumn] + "','"+ (DT_WSTR, 50) (DT_DBTIMESTAMP) @[System::StartTime] + "')"

and then i went to SSIS Packages and did the following at the expression builder:

@[User::Logging_sql_statement] = @[$Project::Parameter]

but instead of getting the expression evaluation of @[$Project::Parameter] value, i only get its value.

For example:

in SSIS Package with name Employees_Table.dtsx and variables (with hardcoded values)

@[User::TableName] = Employees
@[User::TableColumn] = EmployeeName

I want the following

@[User::Logging_sql_statement] = Expression Evaluation(@[$Project::Parameter]) 

to give the following value as a result:

Insert into dbo.Log_Table (table_name,delta_column_name,start_time) 
values ('Employees','EmployeeName','yyyy-mm-dd hh:mm:ss')

instead of the above, I get

Insert into dbo.Log_Table (table_name,delta_column_name,start_time) 
values ('" + @[User::TableName] + "','"+ @[User::TableColumn] + "','"+ (DT_WSTR, 50) (DT_DBTIMESTAMP) @[System::StartTime] + "')

is there a way to achieve this?

Answer 1

As I know, you can not use expression for project parameters, because of that, everything you wrote in value of project parameters, it is shown in the package parameters that you used.