Source code for langchain_community.document_loaders.oracleadb_loader
from typing import Any, Dict, List, Optional
from langchain_core.documents import Document
from langchain_community.document_loaders.base import BaseLoader
[docs]class OracleAutonomousDatabaseLoader(BaseLoader):
"""从Oracle adb加载
自主数据库连接可以通过connection_string或tns名称进行。
对于TLS连接,需要提供wallet_location和wallet_password。
每个文档将代表查询结果的一行。
列将被写入构造函数中的`page_content`和'metadata','metadata'默认为None。"""
[docs] def __init__(
self,
query: str,
user: str,
password: str,
*,
schema: Optional[str] = None,
tns_name: Optional[str] = None,
config_dir: Optional[str] = None,
wallet_location: Optional[str] = None,
wallet_password: Optional[str] = None,
connection_string: Optional[str] = None,
metadata: Optional[List[str]] = None,
):
"""初始化方法
:param query: 要执行的SQL查询
:param user: 用户名
:param password: 用户密码
:param schema: 数据库中要运行的模式
:param tns_name: tnsname.ora中的TNS名称
:param config_dir: 配置文件目录(tnsname.ora,钱包)
:param wallet_location: 钱包位置
:param wallet_password: 钱包密码
:param connection_string: 连接到ADB实例的连接字符串
:param metadata: 文档中使用的元数据
"""
# Mandatory required arguments.
self.query = query
self.user = user
self.password = password
# Schema
self.schema = schema
# TNS connection Method
self.tns_name = tns_name
self.config_dir = config_dir
# Wallet configuration is required for mTLS connection
self.wallet_location = wallet_location
self.wallet_password = wallet_password
# Connection String connection method
self.connection_string = connection_string
# metadata column
self.metadata = metadata
# dsn
self.dsn: Optional[str]
self._set_dsn()
def _set_dsn(self) -> None:
if self.connection_string:
self.dsn = self.connection_string
elif self.tns_name:
self.dsn = self.tns_name
def _run_query(self) -> List[Dict[str, Any]]:
try:
import oracledb
except ImportError as e:
raise ImportError(
"Could not import oracledb, "
"please install with 'pip install oracledb'"
) from e
connect_param = {"user": self.user, "password": self.password, "dsn": self.dsn}
if self.dsn == self.tns_name:
connect_param["config_dir"] = self.config_dir
if self.wallet_location and self.wallet_password:
connect_param["wallet_location"] = self.wallet_location
connect_param["wallet_password"] = self.wallet_password
try:
connection = oracledb.connect(**connect_param)
cursor = connection.cursor()
if self.schema:
cursor.execute(f"alter session set current_schema={self.schema}")
cursor.execute(self.query)
columns = [col[0] for col in cursor.description]
data = cursor.fetchall()
data = [dict(zip(columns, row)) for row in data]
except oracledb.DatabaseError as e:
print("Got error while connecting: " + str(e)) # noqa: T201
data = []
finally:
cursor.close()
connection.close()
return data
[docs] def load(self) -> List[Document]:
data = self._run_query()
documents = []
metadata_columns = self.metadata if self.metadata else []
for row in data:
metadata = {
key: value for key, value in row.items() if key in metadata_columns
}
doc = Document(page_content=str(row), metadata=metadata)
documents.append(doc)
return documents