Getting all Tasks with Variables (Process and Task Variables) - Bad performing query and 20K row limit

Passing in offset = 0. maxResults = 5,000

taskService.createTaskQuery().includeProcessVariables()
.includeTaskVariables().orderByTaskCreateTime().asc().taskCandidateGroupIn(profiles).listPage(offset, count)

The API call above creates this query which is vary inefficient. Why not do a union if Process Variables and Task Variables are both included? Also why does it limit to 20K rows? This seems like a bug. This will never render 5,000 tasks at this point if you have say 20 variables for each task. This would likely only return 1,000 tasks in this scenario.

select RES.*, VAR.ID_ as VAR_ID_, VAR.NAME_ as VAR_NAME_, VAR.TYPE_ as VAR_TYPE_, VAR.REV_ as VAR_REV_, VAR.PROC_INST_ID_ as VAR_PROC_INST_ID_, VAR.EXECUTION_ID_ as VAR_EXECUTION_ID_, VAR.TASK_ID_ as VAR_TASK_ID_, VAR.BYTEARRAY_ID_ as VAR_BYTEARRAY_ID_, VAR.DOUBLE_ as VAR_DOUBLE_, VAR.TEXT_ as VAR_TEXT_, VAR.TEXT2_ as VAR_TEXT2_, VAR.LONG_ as VAR_LONG_ from ACT_RU_TASK RES left outer join ACT_RU_VARIABLE VAR ON RES.ID_ = VAR.TASK_ID_ or RES.PROC_INST_ID_ = VAR.EXECUTION_ID_ WHERE RES.ASSIGNEE_ is null and exists(select LINK.ID_ from ACT_RU_IDENTITYLINK LINK where LINK.TYPE_ = 'candidate' and LINK.TASK_ID_ = RES.ID_ and ( LINK.GROUP_ID_ IN ( "processor" ) ) ) order by RES.CREATE_TIME_ asc LIMIT 20000 OFFSET 0;

Why not a union for seperating out Process vs Task Variables???

select RES.*, VAR.ID_ as VAR_ID_, VAR.NAME_ as VAR_NAME_, VAR.TYPE_ as VAR_TYPE_, VAR.REV_ as VAR_REV_, VAR.PROC_INST_ID_ as VAR_PROC_INST_ID_, VAR.EXECUTION_ID_ as VAR_EXECUTION_ID_, VAR.TASK_ID_ as VAR_TASK_ID_, VAR.BYTEARRAY_ID_ as VAR_BYTEARRAY_ID_, VAR.DOUBLE_ as VAR_DOUBLE_, VAR.TEXT_ as VAR_TEXT_, VAR.TEXT2_ as VAR_TEXT2_, VAR.LONG_ as VAR_LONG_ from ACT_RU_TASK RES left outer join ACT_RU_VARIABLE VAR ON RES.PROC_INST_ID_ = VAR.EXECUTION_ID_ and VAR.TASK_ID_ is null WHERE RES.ASSIGNEE_ is null and exists(select LINK.ID_ from ACT_RU_IDENTITYLINK LINK where LINK.TYPE_ = 'candidate' and LINK.TASK_ID_ = RES.ID_ and ( LINK.GROUP_ID_ IN ( "processor" ) ) )
union
select RES.*, VAR.ID_ as VAR_ID_, VAR.NAME_ as VAR_NAME_, VAR.TYPE_ as VAR_TYPE_, VAR.REV_ as VAR_REV_, VAR.PROC_INST_ID_ as VAR_PROC_INST_ID_, VAR.EXECUTION_ID_ as VAR_EXECUTION_ID_, VAR.TASK_ID_ as VAR_TASK_ID_, VAR.BYTEARRAY_ID_ as VAR_BYTEARRAY_ID_, VAR.DOUBLE_ as VAR_DOUBLE_, VAR.TEXT_ as VAR_TEXT_, VAR.TEXT2_ as VAR_TEXT2_, VAR.LONG_ as VAR_LONG_ from ACT_RU_TASK RES left outer join ACT_RU_VARIABLE VAR ON RES.ID_ = VAR.TASK_ID_ WHERE RES.ASSIGNEE_ is null and exists(select LINK.ID_ from ACT_RU_IDENTITYLINK LINK where LINK.TYPE_ = 'candidate' and LINK.TASK_ID_ = RES.ID_ and ( LINK.GROUP_ID_ IN ( "processor" ) ) ) Order by CREATE_TIME_ asc;