def dat_crime(fpath=None):
# Step Zero: Create dat_crime table
raw_crime(fpath=fpath)
dedupe_crime()
src_crime()
src_crime_table = Table('src_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
dat_crime_table = crime_table('dat_chicago_crimes_all', Base.metadata)
dat_crime_table.append_column(Column('chicago_crimes_all_row_id', Integer, primary_key=True))
dat_crime_table.append_column(Column('start_date', TIMESTAMP, server_default=text('CURRENT_TIMESTAMP')))
dat_crime_table.append_column(Column('end_date', TIMESTAMP, server_default=text('NULL')))
dat_crime_table.append_column(Column('current_flag', Boolean, server_default=text('TRUE')))
dat_crime_table.append_constraint(UniqueConstraint('id', 'start_date'))
dat_crime_table.create(bind=engine, checkfirst=True)
new_cols = ['start_date', 'end_date', 'current_flag', 'chicago_crimes_all_row_id']
dat_ins = dat_crime_table.insert()\
.from_select(
[c for c in dat_crime_table.columns.keys() if c not in new_cols],
select([c for c in src_crime_table.columns])
)
conn = engine.contextual_connect()
res = conn.execute(dat_ins)
cols = crime_master_cols(dat_crime_table)
master_ins = MasterTable.insert()\
.from_select(
[c for c in MasterTable.columns.keys() if c != 'master_row_id'],
select(cols)\
.select_from(dat_crime_table)
)
conn = engine.contextual_connect()
res = conn.execute(master_ins)
return 'DAT crime created'
def chg_crime():
# Step Seven: Find updates
dat_crime_table = Table('dat_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
src_crime_table = Table('src_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
chg_crime_table = Table('chg_chicago_crimes_all', Base.metadata,
Column('id', Integer, primary_key=True),
extend_existing=True)
chg_crime_table.drop(bind=engine, checkfirst=True)
chg_crime_table.create(bind=engine)
src_cols = [c for c in src_crime_table.columns if c.name not in ['id', 'start_date', 'end_date']]
dat_cols = [c for c in dat_crime_table.columns if c.name not in ['id', 'start_date', 'end_date']]
and_args = []
for s, d in zip(src_cols, dat_cols):
ors = or_(s != None, d != None)
ands = and_(ors, s != d)
and_args.append(ands)
ins = chg_crime_table.insert()\
.from_select(
['id'],
select([src_crime_table.c.id])\
.select_from(src_crime_table.join(dat_crime_table,
src_crime_table.c.id == dat_crime_table.c.id))\
.where(or_(
and_(dat_crime_table.c.current_flag == True,
and_(or_(src_crime_table.c.id != None, dat_crime_table.c.id != None),
src_crime_table.c.id != dat_crime_table.c.id)),
*and_args))
)
conn = engine.contextual_connect()
conn.execute(ins)
return 'Changes found'
def update_dat_crimes():
# Step Five: Update Main Crime table
dat_crime_table = Table('dat_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
src_crime_table = Table('src_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
try:
new_crime_table = Table('new_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
except NoSuchTableError:
return None
excluded_cols = ['end_date', 'current_flag', 'chicago_crimes_all_row_id']
dat_cols = [c for c in dat_crime_table.columns.keys() if c not in excluded_cols]
excluded_cols.append('start_date')
src_cols = [c for c in src_crime_table.columns if c.name not in excluded_cols]
src_cols.append(text("'%s' AS start_date" % datetime.now().strftime('%Y-%m-%d')))
ins = dat_crime_table.insert()\
.from_select(
dat_cols,
select(src_cols)\
.select_from(src_crime_table.join(new_crime_table,
src_crime_table.c.id == new_crime_table.c.id))
)
conn = engine.contextual_connect()
conn.execute(ins)
return 'Crime Table updated'
def _add_location(self, span=None):
"""
Add latitude and longitude from weather station into observations table
"""
start_day, end_day = calendar.monthrange(self.current_year, self.current_month)
range_start = '%s-%s-%s' % (self.current_year, self.current_month, 1)
range_end = '%s-%s-%s' % (self.current_year, self.current_month, end_day)
date_col = 'date'
table_name = 'dat_weather_observations_%s' % span
if span == 'hourly':
date_col = 'datetime'
upd = text("""
UPDATE %s SET
longitude = subq.longitude,
latitude = subq.latitude
FROM (
SELECT
wban_code,
st_x(location) as longitude,
st_y(location) as latitude
FROM weather_stations
) as subq
WHERE %s.wban_code = subq.wban_code
AND %s.%s <= :range_end
AND %s.%s >= :range_start
AND %s.longitude IS NULL
AND %s.latitude IS NULL
""" % (table_name, table_name,
table_name, date_col,
table_name, date_col,
table_name, table_name)
)
conn = engine.contextual_connect()
conn.execute(upd, range_start=range_start, range_end=range_end)
def new_crime():
# Step Four: Find New Crimes
dat_crime_table = Table('dat_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
src_crime_table = Table('src_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
new_crime_table = Table('new_chicago_crimes_all', Base.metadata,
Column('id', Integer, primary_key=True),
extend_existing=True)
new_crime_table.drop(bind=engine, checkfirst=True)
new_crime_table.create(bind=engine)
ins = new_crime_table.insert()\
.from_select(
['id'],
select([src_crime_table.c.id])\
.select_from(src_crime_table.join(dat_crime_table,
src_crime_table.c.id == dat_crime_table.c.id, isouter=True))\
.where(dat_crime_table.c.chicago_crimes_all_row_id == None)
)
conn = engine.contextual_connect()
try:
conn.execute(ins)
return 'New records found'
except TypeError:
# No new records
return None
def _add_location(self, span=None):
"""
Add latitude and longitude from weather station into observations table
"""
start_day, end_day = calendar.monthrange(self.current_year,
self.current_month)
range_start = '%s-%s-%s' % (self.current_year, self.current_month, 1)
range_end = '%s-%s-%s' % (self.current_year, self.current_month,
end_day)
date_col = 'date'
table_name = 'dat_weather_observations_%s' % span
if span == 'hourly':
date_col = 'datetime'
upd = text("""
UPDATE %s SET
longitude = subq.longitude,
latitude = subq.latitude
FROM (
SELECT
wban_code,
st_x(location) as longitude,
st_y(location) as latitude
FROM weather_stations
) as subq
WHERE %s.wban_code = subq.wban_code
AND %s.%s <= :range_end
AND %s.%s >= :range_start
AND %s.longitude IS NULL
AND %s.latitude IS NULL
""" % (table_name, table_name, table_name, date_col, table_name,
date_col, table_name, table_name))
conn = engine.contextual_connect()
conn.execute(upd, range_start=range_start, range_end=range_end)
def update_master_current_flag():
# Step Eight: Update end_date and current_flag in master table
dat_crime_table = Table('dat_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
update = MasterTable.update()\
.values(current_flag=False, end_date=datetime.now().strftime('%Y-%m-%d'))\
.where(MasterTable.c.dataset_row_id == dat_crime_table.c.chicago_crimes_all_row_id)\
.where(dat_crime_table.c.current_flag==False)\
.where(dat_crime_table.c.end_date==date.today())
conn = engine.contextual_connect()
conn.execute(update)
return 'Master table current flag updated'
def update_crime_current_flag():
# Step Seven: Update end_date and current_flag in crime table
dat_crime_table = Table('dat_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
chg_crime_table = Table('chg_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
update = dat_crime_table.update()\
.values(current_flag=False, end_date=datetime.now().strftime('%Y-%m-%d'))\
.where(dat_crime_table.c.id==chg_crime_table.c.id)\
.where(dat_crime_table.c.current_flag == True)
conn = engine.contextual_connect()
conn.execute(update)
return 'Crime table current flag updated'
def _update(self, span=None):
new_table = Table('new_weather_observations_%s' % span,
Base.metadata,
Column('wban_code', String(5)),
keep_existing=True)
dat_table = getattr(self, '%s_table' % span)
src_table = getattr(self, 'src_%s_table' % span)
from_sel_cols = ['wban_code']
if span == 'daily':
from_sel_cols.append('date')
src_date_col = src_table.c.date
dat_date_col = dat_table.c.date
new_table.append_column(Column('date', Date))
new_date_col = new_table.c.date
elif span == 'hourly':
from_sel_cols.append('datetime')
src_date_col = src_table.c.datetime
dat_date_col = dat_table.c.datetime
new_table.append_column(Column('datetime', DateTime))
new_date_col = new_table.c.datetime
new_table.drop(engine, checkfirst=True)
new_table.create(engine)
ins = new_table.insert()\
.from_select(from_sel_cols,
select([src_table.c.wban_code, src_date_col])\
.select_from(src_table.join(dat_table,
and_(src_table.c.wban_code == dat_table.c.wban_code,
src_date_col == dat_date_col),
isouter=True)
).where(dat_table.c.id == None)
)
conn = engine.contextual_connect()
try:
conn.execute(ins)
new = True
except TypeError:
new = False
if new:
ins = dat_table.insert()\
.from_select([c for c in dat_table.columns if c.name != 'id'],
select([c for c in src_table.columns])\
.select_from(src_table.join(new_table,
and_(src_table.c.wban_code == new_table.c.wban_code,
src_date_col == new_date_col)
))
)
conn.execute(ins)
def _update(self, span=None):
new_table = Table('new_weather_observations_%s' % span, Base.metadata,
Column('wban_code', String(5)), keep_existing=True)
dat_table = getattr(self, '%s_table' % span)
src_table = getattr(self, 'src_%s_table' % span)
from_sel_cols = ['wban_code']
if span == 'daily':
from_sel_cols.append('date')
src_date_col = src_table.c.date
dat_date_col = dat_table.c.date
new_table.append_column(Column('date', Date))
new_date_col = new_table.c.date
elif span == 'hourly':
from_sel_cols.append('datetime')
src_date_col = src_table.c.datetime
dat_date_col = dat_table.c.datetime
new_table.append_column(Column('datetime', DateTime))
new_date_col = new_table.c.datetime
new_table.drop(engine, checkfirst=True)
new_table.create(engine)
ins = new_table.insert()\
.from_select(from_sel_cols,
select([src_table.c.wban_code, src_date_col])\
.select_from(src_table.join(dat_table,
and_(src_table.c.wban_code == dat_table.c.wban_code,
src_date_col == dat_date_col),
isouter=True)
).where(dat_table.c.id == None)
)
conn = engine.contextual_connect()
try:
conn.execute(ins)
new = True
except TypeError:
new = False
if new:
ins = dat_table.insert()\
.from_select([c for c in dat_table.columns if c.name != 'id'],
select([c for c in src_table.columns])\
.select_from(src_table.join(new_table,
and_(src_table.c.wban_code == new_table.c.wban_code,
src_date_col == new_date_col)
))
)
conn.execute(ins)
def src_crime():
# Step Three: Create New table with unique ids
raw_crime_table = Table('raw_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
dedupe_crime_table = Table('dedup_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
src_crime_table = crime_table('src_chicago_crimes_all', Base.metadata)
src_crime_table.drop(bind=engine, checkfirst=True)
src_crime_table.create(bind=engine)
ins = src_crime_table.insert()\
.from_select(
src_crime_table.columns.keys(),
select([c for c in raw_crime_table.columns if c.name != 'dup_row_id'])\
.where(raw_crime_table.c.dup_row_id == dedupe_crime_table.c.dup_row_id)
)
conn = engine.contextual_connect()
conn.execute(ins)
return 'Source table created'
def dedupe_crime():
# Step Two: Find duplicate records by ID
raw_crime_table = Table('raw_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
dedupe_crime_table = Table('dedup_chicago_crimes_all', Base.metadata,
Column('dup_row_id', Integer, primary_key=True),
extend_existing=True)
dedupe_crime_table.drop(bind=engine, checkfirst=True)
dedupe_crime_table.create(bind=engine)
ins = dedupe_crime_table.insert()\
.from_select(
['dup_row_id'],
select([func.max(raw_crime_table.c.dup_row_id)])\
.group_by(raw_crime_table.c.id)
)
conn = engine.contextual_connect()
res = conn.execute(ins)
return 'Raw crime deduplicated'
def delete_dataset(self, source_url_hash):
md = session.query(MetaTable).get(source_url_hash)
try:
dat_table = Table(
"dat_%s" % md.dataset_name, Base.metadata, autoload=True, autoload_with=engine, keep_existing=True
)
dat_table.drop(engine, checkfirst=True)
except NoSuchTableError:
pass
master_table = MasterTable.__table__
delete = master_table.delete().where(master_table.c.dataset_name == md.dataset_name)
conn = engine.contextual_connect()
try:
conn.execute(delete)
session.delete(md)
session.commit()
except InternalError, e:
raise delete_dataset.retry(exc=e)
def delete_dataset(self, source_url_hash):
md = session.query(MetaTable).get(source_url_hash)
try:
dat_table = Table('dat_%s' % md.dataset_name, Base.metadata,
autoload=True, autoload_with=engine, keep_existing=True)
dat_table.drop(engine, checkfirst=True)
except NoSuchTableError:
pass
master_table = MasterTable.__table__
delete = master_table.delete()\
.where(master_table.c.dataset_name == md.dataset_name)
conn = engine.contextual_connect()
try:
conn.execute(delete)
session.delete(md)
session.commit()
except InternalError, e:
raise delete_dataset.retry(exc=e)
def update_master():
# Step Six: Update Master table
dat_crime_table = Table('dat_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
try:
new_crime_table = Table('new_chicago_crimes_all', Base.metadata,
autoload=True, autoload_with=engine, extend_existing=True)
except NoSuchTableError:
return None
cols = crime_master_cols(dat_crime_table)
ins = MasterTable.insert()\
.from_select(
[c for c in MasterTable.columns.keys() if c != 'master_row_id'],
select(cols)\
.select_from(dat_crime_table.join(new_crime_table,
dat_crime_table.c.id == new_crime_table.c.id))
)
conn = engine.contextual_connect()
conn.execute(ins)
return 'Master updated'
