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Hi, I have an error when trying to use SUM() in a query.

Request:

SELECT SUM(Amount) FROM Opportunity

Error:

Warning (2) - Invalid argument supplied for foreach() in /var/www/dev.local/system/libraries/salesforce/SforcePartnerClient.php on line 344

Hi all, I have a question why such a query works

SELECT COUNT() FROM OpportunityHistory WHERE OpportunityId IN (SELECT Id FROM Opportunity WHERE CreatedDate = THIS_WEEK)

and such an error

SELECT COUNT_DISTINCT(OpportunityId) FROM OpportunityHistory WHERE OpportunityId IN (SELECT Id FROM Opportunity WHERE CreatedDate = THIS_WEEK)

ERROR:

 Invalid argument supplied for foreach() in /var/www/dev.local/system/libraries/salesforce/SforcePartnerClient.php on line 344

Hi all, I have a question why such a query works

SELECT COUNT() FROM OpportunityHistory WHERE OpportunityId IN (SELECT Id FROM Opportunity WHERE CreatedDate = THIS_WEEK)

and such an error

SELECT COUNT_DISTINCT(OpportunityId) FROM OpportunityHistory WHERE OpportunityId IN (SELECT Id FROM Opportunity WHERE CreatedDate = THIS_WEEK)

ERROR:

 Invalid argument supplied for foreach() in /var/www/dev.local/system/libraries/salesforce/SforcePartnerClient.php on line 344