1. Question 2: How to combine connecting string via parameter?
Answer:
You can include parameter reference in the data source connection string and allow the user to choose a data source for the report. For example, with an expression-based connection string, a user who is running a sales report can select a data source for a particular county before running the report.
The following example illustrates the use of a data source expression in a SQL Server connection string. The example assumes you have created a report parameter named ServerName:
="Data Source=" & Parameters! ServerName.Value & "; initial catalog=AdventureWorks"
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