Slide 11
Slide 11 text
σʔλׂͷنଇΛࢦఆ
/data/2018
/data/2018/12
/data/2018/12/JP
/data/2018/12/JP/Tokyo/001.parquet
auto partition_scheme =
schema({field(“year”, int32()), field(“month”, int32()),
field(“country”, utf8()), field(“city”, utf8())});
ASSERT_OK(discovery->SetPartitionScheme(partition_scheme));
ARROW_OK_AND_ASSIGN(auto datasource, discovery->Finish());
year month country city
=> {“year": 2018}
=> {“year”: 2018, “month”: 12}
=> {“year”: 2018, “month”: 12, “country”: “JP”}
=> {“year”: 2018, “month”: 12,
“country”: “JP”, “city”: “Tokyo”}