"" is not equal to '' in query

this.query().dataSourceTable(tablenum(CustInvoicejour)).addRange(fieldnum(CustInvoicejour,InvoiceId)).value('(CustInvoicejour.InvoiceId == "")');

Right

this.query().dataSourceTable(tablenum(CustInvoicejour)).addRange(fieldnum(CustInvoicejour,InvoiceId)).value("(CustInvoicejour.InvoiceId == '')");

Wrong.