return print_start, print_status, print_done
-def load(session, tables=[], directory=None, drop_tables=False, verbose=False):
+def load(session, tables=[], directory=None, drop_tables=False, verbose=False, safe=True):
"""Load data from CSV files into the given database session.
Tables are created automatically.
`verbose`
If set to True, status messages will be printed to stdout.
+
+ `safe`
+ If set to False, load can be faster, but can corrupt the database if
+ it crashes or is interrupted.
"""
# First take care of verbosity
table_objs = [metadata.tables[name] for name in table_names]
table_objs = sqlalchemy.sql.util.sort_tables(table_objs)
+ # SQLite speed tweaks
+ if not safe and session.connection().dialect.name == 'sqlite':
+ session.connection().execute("PRAGMA synchronous=OFF")
+ session.connection().execute("PRAGMA journal_mode=OFF")
# Drop all tables if requested
if drop_tables:
print_start('Dropping tables')
- for table in reversed(table_objs):
+ for n, table in enumerate(reversed(table_objs)):
table.drop(checkfirst=True)
+ print_status('%s/%s' % (n, len(table_objs)))
print_done()
- for table in table_objs:
+ print_start('Creating tables')
+ for n, table in enumerate(table_objs):
table.create()
+ print_status('%s/%s' % (n, len(table_objs)))
+ print_done()
connection = session.connection()
# Okay, run through the tables and actually load the data now
reader = csv.reader(csvfile, lineterminator='\n')
column_names = [unicode(column) for column in reader.next()]
+ if not safe and session.connection().dialect.name == 'postgresql':
+ """
+ Postgres' CSV dialect is nearly the same as ours, except that it
+ treats completely empty values as NULL, and empty quoted
+ strings ("") as an empty strings.
+ Pokedex dump does not quote empty strings. So, both empty strings
+ and NULLs are read in as NULL.
+ For an empty string in a NOT NULL column, the load will fail, and
+ load will fall back to the cross-backend row-by-row loading. And in
+ nullable columns, we already load empty stings as NULL.
+ """
+ session.commit()
+ not_null_cols = [c for c in column_names if not table_obj.c[c].nullable]
+ if not_null_cols:
+ force_not_null = 'FORCE NOT NULL ' + ','.join('"%s"' % c for c in not_null_cols)
+ else:
+ force_not_null = ''
+ command = "COPY {table_name} ({columns}) FROM '{csvpath}' CSV HEADER {force_not_null}"
+ session.connection().execute(
+ command.format(
+ table_name=table_name,
+ csvpath=csvpath,
+ columns=','.join('"%s"' % c for c in column_names),
+ force_not_null=force_not_null,
+ )
+ )
+ session.commit()
+ print_done()
+ continue
+
# Self-referential tables may contain rows with foreign keys of other
# rows in the same table that do not yet exist. Pull these out and add
# them to the session last
print_done()
+ # SQLite check
+ if session.connection().dialect.name == 'sqlite':
+ session.connection().execute("PRAGMA integrity_check")
+
def dump(session, tables=[], directory=None, verbose=False):