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Direktori : /lib64/python3.8/sqlite3/ |
Current File : //lib64/python3.8/sqlite3/dump.py |
# Mimic the sqlite3 console shell's .dump command # Author: Paul Kippes <kippesp@gmail.com> # Every identifier in sql is quoted based on a comment in sqlite # documentation "SQLite adds new keywords from time to time when it # takes on new features. So to prevent your code from being broken by # future enhancements, you should normally quote any identifier that # is an English language word, even if you do not have to." def _iterdump(connection): """ Returns an iterator to the dump of the database in an SQL text format. Used to produce an SQL dump of the database. Useful to save an in-memory database for later restoration. This function should not be called directly but instead called from the Connection method, iterdump(). """ cu = connection.cursor() yield('BEGIN TRANSACTION;') # sqlite_master table contains the SQL CREATE statements for the database. q = """ SELECT "name", "type", "sql" FROM "sqlite_master" WHERE "sql" NOT NULL AND "type" == 'table' ORDER BY "name" """ schema_res = cu.execute(q) for table_name, type, sql in schema_res.fetchall(): if table_name == 'sqlite_sequence': yield('DELETE FROM "sqlite_sequence";') elif table_name == 'sqlite_stat1': yield('ANALYZE "sqlite_master";') elif table_name.startswith('sqlite_'): continue # NOTE: Virtual table support not implemented #elif sql.startswith('CREATE VIRTUAL TABLE'): # qtable = table_name.replace("'", "''") # yield("INSERT INTO sqlite_master(type,name,tbl_name,rootpage,sql)"\ # "VALUES('table','{0}','{0}',0,'{1}');".format( # qtable, # sql.replace("''"))) else: yield('{0};'.format(sql)) # Build the insert statement for each row of the current table table_name_ident = table_name.replace('"', '""') res = cu.execute('PRAGMA table_info("{0}")'.format(table_name_ident)) column_names = [str(table_info[1]) for table_info in res.fetchall()] q = """SELECT 'INSERT INTO "{0}" VALUES({1})' FROM "{0}";""".format( table_name_ident, ",".join("""'||quote("{0}")||'""".format(col.replace('"', '""')) for col in column_names)) query_res = cu.execute(q) for row in query_res: yield("{0};".format(row[0])) # Now when the type is 'index', 'trigger', or 'view' q = """ SELECT "name", "type", "sql" FROM "sqlite_master" WHERE "sql" NOT NULL AND "type" IN ('index', 'trigger', 'view') """ schema_res = cu.execute(q) for name, type, sql in schema_res.fetchall(): yield('{0};'.format(sql)) yield('COMMIT;')