1977765 - [SAP IQ] Internal Error "s_ohcidx.cxx:5361" happened while running a delete statement.

1. while running a delete statement, a non-fatal IQ internal error happened.
   IQ optimizer choses a mid method for deleting a HG index.
   DBCC reports "No error detected" for consistency check of the HG index using sp_iqcheckdb stored procedure.
2. Error message & Stacktrace

[20917]: Delete of 5120347 rows started for table:
Mid Delete Failed for Index OWNER001.TAB001.IDX001: 5120348 Rows Deleted. Expected 5120347.
   
********************************************************
**
**       Non-Fatal IQ Internal Error Detected
**       at s_ohcidx.cxx:5361  on thread 926 (TID 917)
**

_Z13ucstkgentraceii + ............
_Z23StackTraceForThisThreadPKciS0_S0_S0_ + ............
_ZN15hs_idxexceptionC1EPKciNS_12hs_idxerrorsEPK7s_indexjS1_S1_ + ............
_Z20hs_ThrowIdxExceptionPKciN15hs_idxexception12hs_idxerrorsEPK7s_indexjS0_S0_ + ............
_ZN12hs_ohcDelete8CompleteEv + ............
_ZN19s_ohcDeleteIterator8CompleteEv + ............
_ZN6hs_ohc9MidDeleteERK4s_bmiPK14hos_ValueRange + ............
_ZN6hs_ohc6DeleteEPK4s_bmyiiP8s_CKInfoPK14hos_ValueRange + ............
_ZN18hdb_delete_indices12Unit_of_WorkEi + ............
_ZN18hdb_delete_indices21hdb_delete_index_iter8ExecWorkERij + ............
_ZN13workAllocator6DoWorkEj + ............
_ZN13workAllocator7sDoWorkEPS_j + ............
_ZN10hos_thread4MainEv + 0x5e0 at ............
_ZN10hos_lwtask5StartEPS_ + ............
_Z15IQWorkerStarterPv + ............
run_task_body + ............
_ZN8UnixTask8pre_bodyEPv + ............
__pthread_bound_body + ............

   
Exception Thrown from s_ohcidx.cxx:5361, Err# 16, tid 917 origtid 917
   O/S Err#: 0, ErrID: 2068 (hs_idxexception); SQLCode: -1006003, SQLState: 'QBA03', Severity: 23
[20241]: IQ Internal error. Please report this to Sybase IQ support. OWNER001.TAB001.IDX001 14 ???

SAP SYBASE IQ 15.4 SP03 PL7 (15.4 ESD 3.7)

s_ohcidx, delete, mid deleted failed, _ZN12hs_ohcDelete8CompleteEv , KBA , BC-SYB-IQ , Sybase IQ , Problem