from pokedex.db import metadata
import pokedex.db.tables as tables
from pokedex.defaults import get_default_csv_dir
+from pokedex.db.dependencies import find_dependent_tables
def _get_table_names(metadata, patterns):
def print_start(thing):
# Truncate to 66 characters, leaving 10 characters for a success
# or failure message
- truncated_thing = thing[0:66]
+ truncated_thing = thing[:66]
# Also, space-pad to keep the cursor in a known column
num_spaces = 66 - len(truncated_thing)
return print_start, print_status, print_done
-def load(session, tables=[], directory=None, drop_tables=False, verbose=False, safe=True):
+def load(session, tables=[], directory=None, drop_tables=False, verbose=False, safe=True, recursive=False):
"""Load data from CSV files into the given database session.
Tables are created automatically.
`safe`
If set to False, load can be faster, but can corrupt the database if
it crashes or is interrupted.
+
+ `recursive`
+ If set to True, load all dependent tables too.
"""
# First take care of verbosity
if directory is None:
directory = get_default_csv_dir()
+ # XXX why isn't this done in command_load
table_names = _get_table_names(metadata, tables)
table_objs = [metadata.tables[name] for name in table_names]
+
+ if recursive:
+ table_objs.extend(find_dependent_tables(table_objs))
+
table_objs = sqlalchemy.sql.util.sort_tables(table_objs)
# SQLite speed tweaks
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.
+ Postgres' CSV dialect works with our data, if we mark the not-null
+ columns with FORCE NOT NULL.
+ COPY is only allowed for DB superusers. If you're not one, use safe
+ loading (pokedex load -S).
"""
session.commit()
not_null_cols = [c for c in column_names if not table_obj.c[c].nullable]
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}"
+ command = "COPY %(table_name)s (%(columns)s) FROM '%(csvpath)s' CSV HEADER %(force_not_null)s"
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,
- )
+ command % dict(
+ 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
# them to the session last
# ASSUMPTION: Self-referential tables have a single PK called "id"
deferred_rows = [] # ( row referring to id, [foreign ids we need] )
- seen_ids = {} # primary key we've seen => 1
+ seen_ids = set() # primary keys we've seen
# Fetch foreign key columns that point at this table, if any
self_ref_columns = []
for column in table_obj.c:
- if any(_.references(table_obj) for _ in column.foreign_keys):
+ if any(x.references(table_obj) for x in column.foreign_keys):
self_ref_columns.append(column)
new_rows = []
def insert_and_commit():
+ if not new_rows:
+ return
session.connection().execute(insert_stmt, new_rows)
session.commit()
new_rows[:] = []
# May need to stash this row and add it later if it refers to a
# later row in this table
if self_ref_columns:
- foreign_ids = [row_data[_.name] for _ in self_ref_columns]
- foreign_ids = [_ for _ in foreign_ids if _] # remove NULL ids
+ foreign_ids = set(row_data[x.name] for x in self_ref_columns)
+ foreign_ids.discard(None) # remove NULL ids
if not foreign_ids:
# NULL key. Remember this row and add as usual.
- seen_ids[row_data['id']] = 1
+ seen_ids.add(row_data['id'])
- elif all(_ in seen_ids for _ in foreign_ids):
+ elif foreign_ids.issubset(seen_ids):
# Non-NULL key we've already seen. Remember it and commit
# so we know the old row exists when we add the new one
insert_and_commit()
- seen_ids[row_data['id']] = 1
+ seen_ids.add(row_data['id'])
else:
# Non-NULL future id. Save this and insert it later!
# Attempt to add any spare rows we've collected
for row_data, foreign_ids in deferred_rows:
- if not all(_ in seen_ids for _ in foreign_ids):
+ if not foreign_ids.issubset(seen_ids):
# Could happen if row A refers to B which refers to C.
# This is ridiculous and doesn't happen in my data so far
raise ValueError("Too many levels of self-reference! "
session.connection().execute(
insert_stmt.values(**row_data)
)
- seen_ids[row_data['id']] = 1
+ seen_ids.add(row_data['id'])
session.commit()
print_done()