HPI/sql.py
Dima Gerasimov 1a765129cb loading
2019-04-30 13:22:19 +02:00

80 lines
2.4 KiB
Python
Executable file

#!/usr/bin/env python3
from pathlib import Path
from itertools import islice
import logging
from location import _load_locations, Location, get_logger
import sqlalchemy as sa # type: ignore
from kython import ichunks
# TODO wonder if possible to extract schema automatically?
def xx_obj():
return Location(
dt=sa.types.TIMESTAMP(timezone=True), # TODO tz?
# TODO FIXME utc seems to be lost.. doesn't sqlite support it or what?
lat=sa.Float,
lon=sa.Float,
alt=sa.Float, # TODO nullable
tag=sa.String,
)
def make_schema(obj):
return [sa.Column(col, tp) for col, tp in obj._asdict().items()]
def save_locs(db_path: Path):
db = sa.create_engine(f'sqlite:///{db_path}')
engine = db.connect() # TODO do I need to tear anything down??
meta = sa.MetaData(engine)
schema = make_schema(xx_obj())
sa.Table('locations', meta, *schema)
meta.create_all()
table = sa.table('locations', *schema)
with Path('/L/tmp/loc/LocationHistory.json').open('r') as fo:
# locs = list(_load_locations(fo))
# TODO fuck. do I really need to split myself??
# sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) too many SQL variables
# TODO count deprecated??
for chunk in ichunks(_load_locations(fo), 10000):
engine.execute(table.insert().values(chunk))
print(engine.execute(table.count()).fetchone())
# TODO maintain order during insertion?
def iter_db_locs(db_path: Path):
db = sa.create_engine(f'sqlite:///{db_path}')
engine = db.connect() # TODO do I need to tear anything down??
meta = sa.MetaData(engine)
schema = make_schema(xx_obj())
sa.Table('locations', meta, *schema)
meta.create_all()
table = sa.table('locations', *schema)
datas = engine.execute(table.select()).fetchall()
yield from (Location(**d) for d in datas)
def main():
from kython import setup_logzero
setup_logzero(get_logger(), level=logging.DEBUG)
db_path = Path('test3.sqlite')
# if db_path.exists():
# db_path.unlink()
locs = iter_db_locs(db_path)
print(len(list(locs)))
# TODO is it quicker to insert anyway? needs unique policy
# ok, very nice. the whold db is just 20mb now
# nice, and loads in seconds basically
# TODO FIXME just need to check timezone
if __name__ == '__main__':
main()