How can I merge two outputs of two Linq queries ?

Question

I'm trying to merge these two object but not totally sure how.. Can you help me merge these two result objects?

 //
 // Create Linq Query for all segments in "CognosSecurity"
 //
 var userListAuthoritative = (from c in ctx.CognosSecurities
                             where (c.SecurityType == 1 || c.SecurityType == 2)
                             select new {c.SecurityType, c.LoginName , c.SecurityName}).Distinct();
 //
 // Create Linq Query for all segments in "CognosSecurity"
 //
 var userListAuthoritative3 = (from c in ctx.CognosSecurities
                              where c.SecurityType == 3 || c.SecurityType == 0
                              select new {c.SecurityType , c.LoginName }).Distinct();

I think I see where to go with this... but to answer the question the types of the objects are int, string, string for SecurityType, LoginName , and SecurityName respectively

If you're wondering why I have them broken like this is because I want to ignore one column when doing a distinct. Here are the SQL queries that I'm converting to SQL.

  select distinct SecurityType, LoginName, 'Segment'+'-'+SecurityName
FROM [NFPDW].[dbo].[CognosSecurity]
where SecurityType =1

  select distinct SecurityType, LoginName, 'Business Line'+'-'+SecurityName
FROM [NFPDW].[dbo].[CognosSecurity]
where SecurityType =2

   select distinct SecurityType, LoginName, SecurityName
FROM [NFPDW].[dbo].[CognosSecurity]
where SecurityType in (1,2)

Answer 1

Edit: This assumed they were of the same type -- but they're not.

userListAuthoritative.Concat(userListAuthoritative3);

Answer 2

I assume that you want to keep the results distinct:

var merged = userListAuthoritative.Concat(userListAuthoritative3).Distinct();

And, as Mike Q pointed out, you need to make sure that your types match, either by giving the anonymous types the same signature, or by creating your own POCO class specifically for this purpose.

Edit

If I understand your edit, you want your Distinct to ignore the SecurityName column. Is that correct?

var userListAuthoritative = from c in ctx.CognosSecurities
                            where new[]{0,1,2,3}.Contains(c.SecurityType)
                            group new {c.SecurityType, c.LoginName, c.SecurityName}
                                by new {c.SecurityType, c.LoginName}
                            select g.FirstOrDefault();

Answer 3

I'm not exactly sure what you mean by merge, since you're returning different (anonymous) types from each one. Is there a reason the following doesn't work for you?

var userListAuthoritative = (from c in ctx.CognosSecurities
                         where (c.SecurityType == 1 || c.SecurityType == 2 || c.SecurityType == 3 || c.SecurityType == 0)
                         select new {c.SecurityType, c.LoginName , c.SecurityName}).Distinct();

Answer 4

Try below code, you might need to implement IEqualityComparer<T> in your ctx type.

var merged = userListAuthoritative.Union(userListAuthoritative3);