Hi Bob I have encountered same issue 

Hi I have an apex classes which is scheduled 1a.m everyday. The apex class aborts and gives the following error

First error: SQLException [java.sql.SQLException: ORA-01013: user requested cancel of current operation
: select /*AggJoin*/ "AccountId",
"Id",
"Subject",
"OwnerId",
"RecordType__c",
"Purpose__c",
"WhoId",
"ActivityDate",
"ActivityDate.AUX",

Here is my code. Kindly help 

/*
Extension case#03698934
This scheduler will consider only the following Events.
Events where last modify date is yesterday and End date is less then today AND
Profile of Assigned To  = Apartments.com House AC, Apartments.com RM User, Apartments.com Standard User, Gannett Standard User, LA Times Standard User AND
Event Record Type = Standard Event OR (Event Record Type = Event (Contact Optional) AND Level – Type = “Leases 4 Lunch”,” Mgmt Co – Cold Call Visit”,”Property – Cold Call Visit”)
and update the account info on from the selected Events information  

*/

global class ContactLastActivityDateBatch implements Database.Batchable<sObject>{
public String query;

global database.querylocator start(Database.BatchableContext BC){
    return Database.getQueryLocator(query);
}
    
global void execute(Database.BatchableContext BC, List<sObject> scope){
        List<Account> accList= new List<Account>();
     
       
        for(sObject s : scope){
        
        Account acc = (Account)s;
        System.debug('Rajan Testing date 1'+acc);
         if(acc.ActivityHistories.size() > 0 && (acc.Last_visit_date__c == null || acc.Last_visit_date__c <= acc.ActivityHistories[0].ActivityDate)){
            try{
                
               ActivityHistory act = acc.ActivityHistories;                 
               acc.Last_visit_subject__c = act.Subject;
               acc.Last_visit_date__c = act.ActivityDate;
               acc.Last_visit_assigned_to__c = act.Owner.Name;
               acc.Last_visit_record_type__c = act.RecordType__c;
               acc.Last_visit_purpose__c = act.Purpose__c;
               acc.Last_visit_level_type__c=act.Level_Type__c;
               acc.Last_visit_description__c=act.Description;
               
               //Populate only if who Id in Event is populated with a Contact Name.
               if(act.whoId != null && string.valueOf(act.whoId).startsWith('003')) 
               acc.Last_visit_contact_name__c = act.whoId;
               else
               acc.Last_visit_contact_name__c = null;
               //System.debug('Rajan Testing date 2'+c.Last_Activity_Date__c + act.ActivityDate);
                 accList.add(acc);             
            }
            catch(Exception ex){
                System.debug(ex.getMessage());
            }
        }
    }
    update accList;
    
    
    }
  global void finish(Database.BatchableContext BC){}  
}

/*Salesforce.com Extension#03698934
This class implements apex schedular interface to update Last Activity Date on Account
*/
global class updateAccountLastActivityDate implements Schedulable
{ 
    global void execute(SchedulableContext ctx){
        
        ContactLastActivityDateBatch accBatch = new ContactLastActivityDateBatch ();
    
        accBatch.query ='select Name, Last_visit_subject__c,Last_visit_level_type__c,Last_visit_description__c,Last_visit_date__c, Last_visit_assigned_to__c, Last_visit_record_type__c, Last_visit_purpose__c,  Last_visit_contact_name__c,'
                        +'(Select Subject,Owner.Name,RecordType__c,Purpose__c, whoId ,AccountId,id,ActivityDate,Level_Type__c,Description from ActivityHistories where '
                        +'Custom_Profile_Name__c in (\'Apartments.com House AC\',\'Apartments.com RM User\',\'Apartments.com Standard User\',\'Gannett Standard User\',\'LA Times Standard User\')'
                        +' AND (RecordType__c=\'Standard Event\'  OR  (RecordType__c=\'Event (Contact Optional)\' AND Level_Type__c in (\'Leases 4 Lunch\',\'Mgmt Co - Cold Call Visit\',\'Property - Cold Call Visit\')))'
                        +' AND ActivityDate <= TODAY'
                        +' AND Isdeleted =false'
                        +' order by ActivityDate desc limit 1) from Account';                                   
                        
                         
        ID batchprocessid = Database.executeBatch(accBatch);
       
    }