Using wildcards for column names in dynamic soql in apex

Question

I have a scenario where my columns names can be of form genesis__prod__c/docgen__prod__c/lnd__prod__c,etc depending upon which package is using my solution package. Here genesis, docgen and lnd are different product packages using my solution.

My solution needs to fetch any of these fields (genesis__prod__c/docgen__prod__c/lnd__prod__c) from their respective sObjects in their products.

I want to construct a generic query which will omit the namespace using a wildcard and only look for prod__c in specified sObject. With such a solution, I wouldn't have to hardcode any namespace in my query.

For example, I don't want to form my query like this

String query = 'select Id,Name,docgen__CL_Product__c from '+ sObjectType + ' where id= \'' + appId + '\'';
List<sObject> runtimeDeterminedObject = Database.query(query+' LIMIT 1');

Here I have specifically mentioned docgen__CL_Product__c name to be fetched from a runtime resolved sObject name sObjectType wrt an appId

How can I form a query where I do not have to provide namespace docgen,genesis before prod__c. I do not want to write if-else for each product which can utilize my package.

Answer 1

Nope. You can't do it. Every field in your SELECT clause must be one, specific field. You have to loop through the object's field map and pull in the fields individually.

List<String> prodFields = new List<String>();
for (String field : sObjectType.getDescribe().fields.getMap().keySet())
    if (field.contains('__prod__c'))
        prodFields.add(field);

Answer 2

I am not sure in context of managed package, but if you can get the namespace then you can construct your query based on the namespace of the org.

Update:

This approach will work if you are installing a class through your package.

Assume the class name is 'namespace', you can get the raw namespace by using:

nameSpacePrefix =namespace.class.getName().substringBefore('namespace').substringBefore('.');

Look at mattandneil's answer for other ways to get the namespace prefix:

Namespace Prefix in JavaScript and Apex within Installed Package

public class namespace {

    public static string nameSpacePrefix;
    public static String query;
        public namespace(){
         nameSpacePrefix= '';
        }
        
        public static string constructmysoqlquery(){
           nameSpacePrefix= [SELECT NamespacePrefix FROM Organization].NamespacePrefix;
           // could be handled better by adding the namespaces in a custom setting.
           
            set<string> namespaceset = new  set<string>{'genesis','docgen','lnd'};
               if(namespaceset.contains(nameSpacePrefix)){
                   query = 'select Id,Name,'+nameSpacePrefix+'_Product__c from '+ sObjectType + ' where id= \'' + appId + '\'';;
               }
        return query;
        }
        
    }