c# - Check to see if row exists before adding it? -

i have certification process. right add people certification table if certified item in question.

on view page, have procedureid , there active directory username. pass controller method adds them table.

however if exist don't need add them update certification date , leave else alone.

what having trouble checking if exist.

[httppost] public actionresult addcertification(int procedureid, formcollection collection) {     string[] certifiedusers = collection["members"].split(',');      ipacs_certification ipacs_certification = new ipacs_certification();      foreach (var item in certifiedusers)     {         // certification exist?         ipacs_certification doesexist = db.ipacs_certification.where(m => m.adusername == item && m.procedureid == procedureid).select(m => m);         ipacs_certification.procedureid = procedureid;         ipacs_certification.certifieddate = datetime.now;         ipacs_certification.adusername = item;          db.ipacs_certification.add(ipacs_certification);         db.savechanges();     }      return redirecttoaction("addcertification"); } 

my table contains following columns.

certid (key identity)
procedureid (fkey procedure table)
certifieddate datetime
adusername nvarchar

if exist should able grab row adusername , procedureid , grab unique single record. if exist need update certifieddate todays date. if record not found need perform above add.

the above code has error:

ipacs_certification doesexist = db.ipacs_certification.where(m => m.adusername == item && m.procedureid == procedureid).select(m => m); 

cannot implicitly convert type system.linq.iqueryable ipacs_certification. know missing there.

can check if entry exist following way:

bool exists = db.ipacs_certification.firstordefault(m => m.adusername == item && m.procedureid == procedureid) != null; 

if exist , want use data row rather way:

ipacs_certification certification= db.ipacs_certification.firstordefault(m => m.adusername == item && m.procedureid == procedureid);  if(certification != null) {   // exists, stuff data object } else {   //doesn't exist, save certification }