def create_table(database_name,table_name,rows):
if is_database_exist(database_name) == False:
print 'The database named %s was not exists!' % (database_name)
return False
if is_table_exist(dbname = database_name,table_name = table_name) == True:
print 'The table named %s has already exists!' % (table_name)
return False
if whether_can_new_table_object(table_name,rows) == False:
#print r' Your input was wrong.'
return False
database_path = get_data_base_path(database_name)
table_name_append_suffix = table_name + TABLE_INFO_FILE_SUFFIX
table_info = ''
for row in rows:
table_info += '\t'.join(row)
table_info += '\n'
write_to_file(string = table_info,file_path = r'%s\%s' % (database_path ,table_name_append_suffix))
write_to_file(string = '',file_path = r'%s\%s%s' % (database_path ,table_name,TABLE_DATA_FILE_SUFFIX))
append_string_to_file(string = table_name + '\n', file_path = r'%s\%s' % (database_path,TABLES_NAME_FILE))
#print 'Table created successful!'
return True
def drop_row(database_name, table_name, row_name):
if is_db_and_tb_both_exist(database_name, table_name) == False:
return False
if is_row_exist(database_name, table_name, row_name ) == False:
print 'The row named %s has not exists!' % (row_name)
return False
table_info_txt_path = get_table_info_txt_path(database_name, table_name)
table_info_list = get_object_from_file_append_to_list(table_info_txt_path)
after_drop_info = get_drop_row_string_from_infolist(table_info_list,row_name)
write_to_file(after_drop_info, table_info_txt_path)
return True
def modify_row_from_table(database_name, table_name, row_name,new_type):
if new_type not in ROW_TUPLE:
return False
if is_db_and_tb_both_exist(database_name, table_name) == False:
return False
if is_row_exist(database_name, table_name, row_name ) == False:
print 'The row named %s has not exists!' % (row_name)
return False
table_info_txt_path = get_table_info_txt_path(database_name, table_name)
table_info_list = get_object_from_file_append_to_list(table_info_txt_path)
after_modified_info = get_modified_row_string_from_infolist(table_info_list, row_name , new_type)
write_to_file(after_modified_info, table_info_txt_path)
return True
def create_database(database_name,databases_file_path = DATABASE_FILE_PATH):
if is_database_exist(database_name) == True:
print 'The database named %s was already exists!' % (database_name)
return False
new_database_path = get_data_base_path(database_name)
try:
os.mkdir(new_database_path)
except:
#print 'can not built the database!'
return False
write_to_file(string = '',file_path = r'%s\%s' % (new_database_path,TABLES_NAME_FILE))
append_string_to_file(string = database_name + '\n', file_path = databases_file_path)
return True
def drop_database(database_name):
if not object_in_file_list(obj = database_name , file_path = DATABASE_FILE_PATH):
print 'The database had not exists!'
return False
database_path = get_database_path(database_name)
try:
shutil.rmtree(database_path)
except:
#print 'Drop error!'
return False
databases = get_object_from_file_extend_to_list(DATABASE_FILE_PATH)
after_drop_databases = [db for db in databases if db != database_name]
databases = '\n'.join(after_drop_databases)
write_to_file(string = databases,file_path = DATABASE_FILE_PATH)
if default_variable.CURRENT_DB == database_name:
default_variable.CURRENT_DB = None
return True
def drop_table(database_name,table_name):
if is_table_exist(database_name,table_name) == False:
print 'The table has not exists!'
return False
table_info_path = get_table_info_txt_path(database_name,table_name)
table_data_path = get_table_data_file_path(database_name,table_name)
all_tables_info_path = get_all_table_name_info_txt_path(database_name)
try:
os.remove(table_info_path)
os.remove(table_data_path)
except:
#print 'Drop error!'
return False
tables = get_object_from_file_extend_to_list(all_tables_info_path)
after_drop_tables = [tb for tb in tables if tb != table_name]
tables = '\n'.join(after_drop_tables)
write_to_file(string = tables,file_path = all_tables_info_path)
return True