def delete_records(self, criteria: List[db_api.SelectionCriteria]) -> None:
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
num_of_files = data[self.name]["num_of_files"]
primary_key = data[self.name]["key_field_name"]
for file in range(num_of_files):
file_data = json_func.read_from_json(f"{db_api.DB_ROOT}/{self.name}{file + 1}.json")
keys_to_delete = []
for key, value in file_data.items():
flag = 0
for c in criteria:
if c.field_name == primary_key:
if key in file_data.keys():
if not ops[c.operator](int(key), int(c.value)):
flag = 1
break
elif key in file_data.keys():
if not ops[c.operator](int(value[c.field_name]), int(c.value)):
flag = 1
break
if not flag:
keys_to_delete.append(key)
for key in keys_to_delete:
del file_data[key]
data[self.name]["num_of_lines"] -= 1
update_delete_indexes(data, self.name, key)
json_func.write_to_json(f"{db_api.DB_ROOT}/{self.name}{file + 1}.json", file_data)
json_func.write_to_json(f"{db_api.DB_ROOT}/db.json", data)
def get_record(self, key: Any) -> Dict[str, Any]:
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
num_of_files = data[self.name]["num_of_files"]
for file in range(num_of_files):
json_data = json_func.read_from_json(f"{db_api.DB_ROOT}/{self.name}{file + 1}.json")
for k in json_data.keys():
if k == str(key):
return json_data[k]
raise ValueError
def update_record(self, key: Any, values: Dict[str, Any]) -> None:
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
primary_key = data[self.name]["key_field_name"]
json_path = get_indexes(f'{db_api.DB_ROOT}/{self.name}IndexBy{primary_key}.db', key)
json_data = json_func.read_from_json(json_path)
for k in json_data.keys():
if k == str(key):
for key, value in values.items():
json_data[k][key] = value
json_func.write_to_json(json_path, json_data)
return None
raise ValueError
def create_index(self, field_to_index: str) -> None:
index = {}
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
if field_to_index in data[self.name]["indexes"]:
print("index exist")
return
data[self.name]["indexes"].append(field_to_index)
json_func.write_to_json(f"{db_api.DB_ROOT}/db.json", data)
num_of_files = data[self.name]["num_of_files"]
primary_key = data[self.name]["key_field_name"]
if primary_key == field_to_index:
for file in range(num_of_files):
path = f"{db_api.DB_ROOT}/{self.name}{file + 1}.json"
the_file = open(path)
json_data = json.load(the_file)
for k in json_data.keys():
index[k] = path
else:
for file in range(num_of_files):
path = f"{db_api.DB_ROOT}/{self.name}{file + 1}.json"
the_file = open(path)
json_data = json.load(the_file)
for v in json_data.values():
index[v[field_to_index]] = path
json_func.write_to_json(f'{db_api.DB_ROOT}/{self.name}IndexBy{field_to_index}.db', index)
def insert_record(self, values: Dict[str, Any]) -> None:
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
primary_key = data[self.name]["key_field_name"]
flag = None
try:
flag = self.get_record(values[primary_key])
except ValueError:
new_record = {
values[primary_key]:
{k: str(v)
for k, v in values.items() if k != primary_key}
}
if data[self.name]["num_of_lines"] % 10 == 0 and data[
self.name]["num_of_lines"] != 0:
data[self.name]["num_of_files"] += 1
json_func.write_to_json(
f"{db_api.DB_ROOT}/{self.name}{data[self.name]['num_of_files']}.json",
new_record)
else:
json_func.add_line_to_json(
f"db_files/{self.name}{data[self.name]['num_of_files']}.json",
values[primary_key], new_record[values[primary_key]])
data[self.name]["num_of_lines"] += 1
json_func.write_to_json(f"{db_api.DB_ROOT}/db.json", data)
update_insert_indexes(
data, self.name, values,
f"db_files/{self.name}{data[self.name]['num_of_files']}.json")
if flag is not None:
raise ValueError
def update_delete_indexes(data, name, index):
if index in data[name]["indexes"]:
json_data = json_func.read_from_json(
f'{db_api.DB_ROOT}/{name}IndexBy{index}.db')
del json_data[str(index)]
json_func.write_to_json(f'{db_api.DB_ROOT}/{name}IndexBy{index}.db',
json_data)
def update_insert_indexes(data, name, values, path):
for index in data[name]["indexes"]:
json_data = json_func.read_from_json(
f'{db_api.DB_ROOT}/{name}IndexBy{index}.db')
json_data[str(values[index])] = path
json_func.write_to_json(f'{db_api.DB_ROOT}/{name}IndexBy{index}.db',
json_data)
def delete_table(self, table_name: str) -> None:
num_of_files = json_func.delete_table_from_json(table_name)
for file in range(num_of_files):
path = f"db_files/{table_name}{file + 1}.json"
os.remove(path)
data = json_func.read_from_json(f"db_files/db.json")
data["num_of_tables"] -= 1
json_func.write_to_json(f"db_files/db.json",data)
def delete_record(self, key: Any) -> None:
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
primary_key = data[self.name]["key_field_name"]
json_path = get_indexes(f'{db_api.DB_ROOT}/{self.name}IndexBy{primary_key}.db', key)
flag = json_func.delete_if_apear(json_path, key)
if flag == 0:
raise ValueError
data[self.name]["num_of_lines"] -= 1
update_delete_indexes(data, self.name, key)
json_func.write_to_json(f"{db_api.DB_ROOT}/db.json", data)
def query_table(self, criteria: List[db_api.SelectionCriteria]) \
-> List[Dict[str, Any]]:
data = json_func.read_from_json(f"{db_api.DB_ROOT}/db.json")
num_of_files = data[self.name]["num_of_files"]
primary_key = data[self.name]["key_field_name"]
list_to_return = []
for file in range(num_of_files):
file_data = json_func.read_from_json(f"{db_api.DB_ROOT}/{self.name}{file + 1}.json")
for key, value in file_data.items():
flag = 0
for c in criteria:
if c.field_name == primary_key:
if not ops[c.operator](int(key), int(c.value)):
flag = 1
break
elif not ops[c.operator](value[c.field_name], c.value):
flag = 1
break
if not flag:
list_to_return.append(value)
return list_to_return
def get_record(self, key: Any) -> Dict[str, Any]:
db_meta_data = read_db_meta_data()
num_of_files = db_meta_data[self.name]['num_of_files']
for file_num in range(num_of_files):
file_data = read_from_json(
f"db_files/{self.name}{file_num + 1}.json")
for k in file_data.keys():
if k == str(key):
return file_data[k]
raise ValueError
def del_if_record_appear(path, key):
file_data = read_from_json(path)
record_exist = False
for k in file_data.keys():
if k == str(key):
record_exist = True
del_key = k
break
if record_exist:
del file_data[del_key]
write_to_json(path, file_data)
return record_exist
def update_record(self, key: Any, values: Dict[str, Any]) -> None:
db_meta_data = read_db_meta_data()
num_of_files = db_meta_data[self.name]['num_of_files']
for file_num in range(num_of_files):
file_data = read_from_json(
f"db_files/{self.name}{file_num + 1}.json")
for k in file_data.keys():
if k == str(key):
for field, val in values.items():
file_data[k][field] = val
write_to_json(f"db_files/{self.name}{file_num + 1}.json",
file_data)
return None
raise ValueError
def query_table(self, criteria: List[SelectionCriteria]) \
-> List[Dict[str, Any]]:
db_meta_data = read_db_meta_data()
num_of_files = db_meta_data[self.name]['num_of_files']
primary_key = db_meta_data[self.name]['key_field_name']
records_to_return = []
for file_num in range(num_of_files):
file_data = read_from_json(
f"db_files/{self.name}{file_num + 1}.json")
for key, value in file_data.items():
for c in criteria:
if c.field_name == primary_key:
if not ops[c.operator](int(key), int(c.value)):
break
elif not ops[c.operator](value[c.field_name], c.value):
break
records_to_return.append(value)
return records_to_return
def delete_records(self, criteria: List[SelectionCriteria]) -> None:
db_meta_data = read_db_meta_data()
num_of_files = db_meta_data[self.name]['num_of_files']
primary_key = db_meta_data[self.name]['key_field_name']
for file_num in range(num_of_files):
keys_to_delete = []
file_data = read_from_json(
f"db_files/{self.name}{file_num + 1}.json")
for key, value in file_data.items():
if meets_all_the_criteria(file_data, key, value, primary_key,
criteria):
keys_to_delete.append(key)
for key in keys_to_delete:
del file_data[key]
db_meta_data[self.name]['num_of_lines'] -= 1
write_to_json(f"db_files/{self.name}{file_num + 1}.json",
file_data)
update_db_meta_data(db_meta_data)
def read_db_meta_data():
return read_from_json("db_files/db.json")
def num_tables(self) -> int:
return json_func.read_from_json("db_files/db.json")["num_of_tables"]
def get_table(self, table_name: str) -> DBTable:
data = json_func.read_from_json("db_files/db.json")[table_name]
return DBTable(table_name, convert_to_db_fields(data["fields"]), data["key_field_name"])
def count(self) -> int:
return json_func.read_from_json(f"db_files/db.json")[self.name]["num_of_lines"]
def get_indexes(path, key):
json_data = json_func.read_from_json(path)
return json_data[str(key)]
def get_tables_names(self) -> List[Any]:
data = json_func.read_from_json("db_files/db.json")
return [name for name in data.keys() if name != "num_of_tables"]
def get_input_and_search(data, trie):
while 1:
sentence_for_search = ""
while 1:
sentence_for_search += input(
f"enter your search term . # for new search. * for exit: {sentence_for_search}"
)
if sentence_for_search:
if sentence_for_search[-1] == "#":
print("---------type a new search---------")
break
if sentence_for_search[-1] == "*":
break
if auto_complete(trie, data, sentence_for_search) == 0:
print("---------not found :( type a new search---------")
break
if sentence_for_search[-1] == "*":
break
if __name__ == '__main__':
"""offline:
data = dict()
trie = create_db()
init_tree(trie, data)"""
trie = read_from_json("trie.json")
data = read_from_json("data.json")
get_input_and_search(data, trie)
