def _check_proc_keys(merged_procs_par, schema):
    """Diagnostic for _assign_proc_keys."""
    crit1 = merged_procs_par['TimeGenerated_orig_par'].isin(merged_procs_par
        [schema.time_stamp])
    crit2 = merged_procs_par['EffectiveLogonId'].isin(merged_procs_par[
        schema.logon_id])
    if schema.target_logon_id:
        c2a = merged_procs_par['EffectiveLogonId'].isin(merged_procs_par[
            schema.target_logon_id])
    crit3 = merged_procs_par['parent_proc_lc'].isin(merged_procs_par[
        'new_process_lc'])
    crit4 = merged_procs_par[schema.process_id].isin(merged_procs_par[
        schema.parent_id])
    crit5 = merged_procs_par['parent_key'].isin(merged_procs_par.index)
    crit6 = merged_procs_par['parent_key'].isna()
    print('has parent time', len(merged_procs_par[crit1]))
    print('effectivelogonId in subjectlogonId', len(merged_procs_par[crit2]))
    if schema.target_logon_id:
        print('effectivelogonId in targetlogonId', len(merged_procs_par[c2a]))
    print('parent_proc_lc in procs', len(merged_procs_par[crit3]))
    print('ProcessId in ParentProcessId', len(merged_procs_par[crit4]))
    print('Parent_key in proc_key', len(merged_procs_par[crit5]))
    print('Parent_key not in proc_key', len(merged_procs_par[~crit5]))
    print('Parent_key is NA', len(merged_procs_par[crit6]))
