X-Git-Url: http://git.veekun.com/zzz-pokedex.git/blobdiff_plain/7323dd76007f16915391386822a7bd8a3a58ebab..c5e4e9b0d6d1564cd98a50be4ffd2c95c6301a25:/pokedex/db/load.py diff --git a/pokedex/db/load.py b/pokedex/db/load.py index b17438d..a6e9d4a 100644 --- a/pokedex/db/load.py +++ b/pokedex/db/load.py @@ -95,7 +95,7 @@ def _get_verbose_prints(verbose): 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. @@ -115,6 +115,10 @@ def load(session, tables=[], directory=None, drop_tables=False, verbose=False): `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 @@ -128,16 +132,24 @@ def load(session, tables=[], directory=None, drop_tables=False, verbose=False): 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 @@ -160,6 +172,36 @@ def load(session, tables=[], directory=None, drop_tables=False, verbose=False): 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 @@ -179,7 +221,7 @@ def load(session, tables=[], directory=None, drop_tables=False, verbose=False): session.commit() new_rows[:] = [] - progress = "{0}%".format(100 * csvfile.tell() // csvsize) + progress = "%d%%" % (100 * csvfile.tell() // csvsize) print_status(progress) for csvs in reader: @@ -251,6 +293,10 @@ def load(session, tables=[], directory=None, drop_tables=False, verbose=False): print_done() + # SQLite check + if session.connection().dialect.name == 'sqlite': + session.connection().execute("PRAGMA integrity_check") + def dump(session, tables=[], directory=None, verbose=False):