SOSL Query Returning Only Empty Lists / No Results

Question

I'm trying to use SOSL to locate Account, Contact, Lead, and Site__c records by Id using a dynamic string of matching ids obtained from Destination__c records. However, I'm not returning any records when the following is run - see below -, and instead only receive back an empty List>(), even though I know the records exist. I tried adding a wild card to the Ids in the string clause in case it was a matter of not being able to match between a 15 char and an 18 char Id, but that didn't seem to have an effect.

 private static Map<sObject, Destination__c> getReferenceRecords(List<Destination__c> destinations){
    List<Id> referenceIds = new List<Id>();
    String refIdsString = '';

    /* Add all the valid reference Ids from the destinations to a string to be used in a dynamic SOSL query*/
    for(Destination__c destination : destinations){
        refIdsString += destination.reference_id__c + '*\\\' OR \\\'';
    }

    refIdsString = refIdsString.removeEnd('*\\\' OR \\\'');

    /*Query all the reference objects */
    String query = 'FIND {\\\'' + refIdsString + '*\\\'} IN ALL FIELDS RETURNING Account(Id, Name, ShippingAddress), Contact(Id, Name, MailingAddress),'
        +' Lead(Id, Name, Address), Site__c(Id, Name, Street_Address__c, Street_Address_2__c, City__c, State__c, Postal_Code__c, Country__c)';

    System.debug(query);
    List<List<sObject>> queryResults = (List<List<sObject>>)search.query(query);    

    System.debug(queryResults);
    System.debug( (List<Account>) queryResults[0]);
    System.debug( (List<Contact>) queryResults[1]);
    System.debug( (List<Lead>) queryResults[2]);
    System.debug( (List<Site__c>) queryResults[3]);
}

Answer 1

You can't SOSL by ID values. Even though ID values are always "indexed", these are database indexes, not search indexes. Unfortunately, you're going to need to use up to four different queries to get the results you're looking for, or create four lookup fields on the Destination__c object so you can get all the values in a single query (e.g. SELECT Account__r.Name, Lead__r.Name, ...).