Hi,first off all CONGRATULATION - ACTIVITI is really a awesome framework.I´m just implementing an application using Activiti and fiddling for better performance. While doing that I discoverd that Taskquery is rather slow if I have many Tasks. Let me explain:I have 100 Tasks for group "management".I want to list them all and do a TaskQuery:
List<Task> tasks = tasksvc.createTaskQuery().taskCandidateGroup("management").list();
This query issues 1+N SELECT-Statements against the database which is quite slow.1.
select distinct T.* from ACT_RU_TASK T inner join ACT_RU_IDENTITYLINK I on I.TASK_ID_ = T.ID_ WHERE T.ASSIGNEE_ is null and I.TYPE_ = 'candidate' and ( I.GROUP_ID_ IN ( ? ) )
Parameters: management(String)
N times for each Task returned by previos Query
select * from ACT_HI_TASKINST where ID_ = ?
Parameters: 2390(String)
As far as I have seen this is caused by the function "setTaskDefinitionKey" in class TaskEntitiy
public void setTaskDefinitionKey(String taskDefinitionKey) {
this.taskDefinitionKey = taskDefinitionKey;
CommandContext commandContext = Context.getCommandContext();
if(commandContext != null) {
int historyLevel = Context.getProcessEngineConfiguration().getHistoryLevel();
if (historyLevel >= ProcessEngineConfigurationImpl.HISTORYLEVEL_AUDIT) {
HistoricTaskInstanceEntity historicTaskInstance = commandContext.getDbSqlSession().selectById(HistoricTaskInstanceEntity.class, id);
if (historicTaskInstance!=null) {
historicTaskInstance.setTaskDefinitionKey(this.taskDefinitionKey);
}
}
}
}
I have HistoryLevel set to "Audit" to track variable changes. But what is the sense of above code? Variable "historicTaskInstance" isn´t used in this function.(or is there some MyIbatis magic?).Is there a way to improve my query without the N additional SELECT statements?Kind regardsPhilipp Eichhorn
