Community: Add bind variable support for oracle adb docloader (#30937)

PR title:
Community: Add bind variable support for oracle adb docloader
Description:
This PR adds support of using bind variable to oracle adb doc loader
class, including minor document change.
Issue:
N/A
Dependencies:
No new dependencies.

docs/docs/integrations/document_loaders/oracleadb_loader.ipynb

@@ -36,10 +36,7 @@
     "pip install oracledb"
    ],
    "metadata": {
-    "collapsed": false,
-    "pycharm": {
-     "is_executing": true
-    }
+    "collapsed": false
    }
   },
   {
@@ -51,10 +48,7 @@
     "from settings import s"
    ],
    "metadata": {
-    "collapsed": false,
-    "pycharm": {
-     "is_executing": true
-    }
+    "collapsed": false
    }
   },
   {
@@ -97,16 +91,14 @@
     "doc_2 = doc_loader_2.load()"
    ],
    "metadata": {
-    "collapsed": false,
-    "pycharm": {
-     "is_executing": true
-    }
+    "collapsed": false
    }
   },
   {
    "cell_type": "markdown",
    "source": [
-    "With TLS authentication, wallet_location and wallet_password are not required."
+    "With TLS authentication, wallet_location and wallet_password are not required.\n",
+    "Bind variable option is provided by argument \"parameters\"."
    ],
    "metadata": {
     "collapsed": false
@@ -117,6 +109,8 @@
    "execution_count": null,
    "outputs": [],
    "source": [
+    "SQL_QUERY = \"select channel_id, channel_desc from sh.channels where channel_desc = :1 fetch first 5 rows only\"\n",
+    "\n",
     "doc_loader_3 = OracleAutonomousDatabaseLoader(\n",
     "    query=SQL_QUERY,\n",
     "    user=s.USERNAME,\n",
@@ -124,6 +118,7 @@
     "    schema=s.SCHEMA,\n",
     "    config_dir=s.CONFIG_DIR,\n",
     "    tns_name=s.TNS_NAME,\n",
+    "    parameters=[\"Direct Sales\"],\n",
     ")\n",
     "doc_3 = doc_loader_3.load()\n",
     "\n",
@@ -133,6 +128,7 @@
     "    password=s.PASSWORD,\n",
     "    schema=s.SCHEMA,\n",
     "    connection_string=s.CONNECTION_STRING,\n",
+    "    parameters=[\"Direct Sales\"],\n",
     ")\n",
     "doc_4 = doc_loader_4.load()"
    ],

libs/community/langchain_community/document_loaders/oracleadb_loader.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List, Optional, Union
 
 from langchain_core.documents import Document
 
@@ -31,6 +31,7 @@ class OracleAutonomousDatabaseLoader(BaseLoader):
         wallet_password: Optional[str] = None,
         connection_string: Optional[str] = None,
         metadata: Optional[List[str]] = None,
+        parameters: Optional[Union[list, tuple, dict]] = None,
     ):
         """
         init method
@@ -44,6 +45,7 @@ class OracleAutonomousDatabaseLoader(BaseLoader):
         :param wallet_password: password of wallet
         :param connection_string: connection string to connect to adb instance
         :param metadata: metadata used in document
+        :param parameters: bind variable to use in query
         """
         # Mandatory required arguments.
         self.query = query
@@ -67,6 +69,9 @@ class OracleAutonomousDatabaseLoader(BaseLoader):
         # metadata column
         self.metadata = metadata
 
+        # parameters, e.g bind variable
+        self.parameters = parameters
+
         # dsn
         self.dsn: Optional[str]
         self._set_dsn()
@@ -96,7 +101,10 @@ class OracleAutonomousDatabaseLoader(BaseLoader):
             cursor = connection.cursor()
             if self.schema:
                 cursor.execute(f"alter session set current_schema={self.schema}")
-            cursor.execute(self.query)
+            if self.parameters:
+                cursor.execute(self.query, self.parameters)
+            else:
+                cursor.execute(self.query)
             columns = [col[0] for col in cursor.description]
             data = cursor.fetchall()
             data = [