Inserting a List<> in SQL Table

I have an entity "report" whose values i want to insert in a Database table. Following attributes of the Report have to be inserted -

reportID - int
 RoleID - int
 Created_BY = SYSTEM(default)
 CURRENT_TIMESTAMP
 

Now the problem is with the 2nd attribute. I have a report with the LIST<ROLES> attributes. ROLES is a well defined entity which has an ID and a NAME. From this list I have to extract every role and insert each role's ID into the table.

So my query presently looks as below :

INSERT INTO REPORT_MARJORIE_ROLE(REPORT_ID, ROLE_ID, CREATED_BY, CREATED)
 VALUES({0}, {1}, 'SYSTEM', CURRENT_TIMESTAMP)
 

The C# code from where I am parsing these values is as follows :

try
 {
     StringBuilder _objSQL = new StringBuilder();
     _objSQL.AppendFormat(Queries.Report.ReportQueries.ADD_NEW_ROLES, report.ID, "report.MarjorieRoles.Add(MarjorieRole")); 
     _objDBWriteConnection.ExecuteQuery(_objSQL.ToString());
     _objDBWriteConnection.Commit();
     _IsRolesAdded = true;
 }
 

So please guide me how to add roles from C# function

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