Details
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Task
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Status: Closed (View Workflow)
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Major
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Resolution: Won't Do
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None
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None
Description
When data distribution is loaded per datetime
--------------------------------------+
| count(distinct id) | count |
--------------------------------------+
| 46347 | 6153751125 |
--------------------------------------+
select count
from fulldata where id=12675;
----------
| count |
----------
| 442005 |
----------
1 row in set (4.06 sec)
MaxMemPct-0;
NumTempFiles-0;
TempFileSpace-0B;
ApproxPhyI/O-0;
CacheI/O-3005367;
BlocksTouched-3005367;
PartitionBlocksEliminated-0;
MsgBytesIn-88MB;
MsgBytesOut-704KB;
Desc Mode Table TableOID ReferencedColumns PIO LIO PBE Elapsed Rows
BPS PM fulldata 3108 (idProducer) 0 3005367 0 4.008 751344
TAS UM - - - - - - 4.007 1
When data is loaded per id
select count
from fulldataOrdered where id=12675;
----------
| count |
----------
| 442005 |
----------
1 row in set (0.07 sec)
MariaDB [datagenerated]> select calgetstats();
MaxMemPct-0;
NumTempFiles-0;
TempFileSpace-0B;
ApproxPhyI/O-0;
CacheI/O-16384;
BlocksTouched-16384;
PartitionBlocksEliminated-563697;
MsgBytesIn-492KB;
MsgBytesOut-6KB;
Mode-Distributed
Partition elimination does not work in the first distribution
Desc Mode Table TableOID ReferencedColumns PIO LIO PBE Elapsed Rows
BPS PM fulldataordered 3216 (idProducer) 0 16384 582408 0.078 4096
TAS UM - - - - - - 0.076 1
When comparing both results there is a huge diff
MsgBytesIn 88MB and 751344 Rows sent
492KB MsgBytesIn and 4096 Rows sent
It looks that or the condition is not push down or the full block is send to UM and row extract taking place in UM ?