Harrison/sql db chain (#641)

Co-authored-by: Bruno Bornsztein <bruno.bornsztein@gmail.com>

docs/modules/chains/examples/sqlite.ipynb

@@ -266,7 +266,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from langchain.chains.sql_database.base import SQLDatabaseSequentialChain"
+    "from langchain.chains import SQLDatabaseSequentialChain"
    ]
   },
   {
@@ -293,14 +293,22 @@
       "\n",
       "\u001b[1m> Entering new SQLDatabaseSequentialChain chain...\u001b[0m\n",
       "Table names to use:\n",
-      "\u001b[33;1m\u001b[1;3m['Employee', 'Customer']\u001b[0m\n",
+      "\u001b[33;1m\u001b[1;3m['Customer', 'Employee']\u001b[0m\n",
+      "\n",
+      "\u001b[1m> Entering new SQLDatabaseChain chain...\u001b[0m\n",
+      "How many employees are also customers? \n",
+      "SQLQuery:\u001b[32;1m\u001b[1;3m SELECT COUNT(*) FROM Customer c INNER JOIN Employee e ON c.SupportRepId = e.EmployeeId;\u001b[0m\n",
+      "SQLResult: \u001b[33;1m\u001b[1;3m[(59,)]\u001b[0m\n",
+      "Answer:\u001b[32;1m\u001b[1;3m There are 59 employees who are also customers.\u001b[0m\n",
+      "\u001b[1m> Finished chain.\u001b[0m\n",
+      "\n",
       "\u001b[1m> Finished chain.\u001b[0m\n"
      ]
     },
     {
      "data": {
       "text/plain": [
-       "' 0 employees are also customers.'"
+       "' There are 59 employees who are also customers.'"
       ]
      },
      "execution_count": 5,

langchain/chains/__init__.py

@@ -12,7 +12,10 @@ from langchain.chains.pal.base import PALChain
 from langchain.chains.qa_with_sources.base import QAWithSourcesChain
 from langchain.chains.qa_with_sources.vector_db import VectorDBQAWithSourcesChain
 from langchain.chains.sequential import SequentialChain, SimpleSequentialChain
-from langchain.chains.sql_database.base import SQLDatabaseChain
+from langchain.chains.sql_database.base import (
+    SQLDatabaseChain,
+    SQLDatabaseSequentialChain,
+)
 from langchain.chains.transform import TransformChain
 from langchain.chains.vector_db_qa.base import VectorDBQA
 
@@ -35,4 +38,5 @@ __all__ = [
     "TransformChain",
     "MapReduceChain",
     "OpenAIModerationChain",
+    "SQLDatabaseSequentialChain",
 ]

langchain/chains/sql_database/base.py

@@ -109,7 +109,9 @@ class SQLDatabaseSequentialChain(Chain, BaseModel):
         **kwargs: Any,
     ) -> SQLDatabaseSequentialChain:
         """Load the necessary chains."""
-        sql_chain = SQLDatabaseChain(llm=llm, database=database, prompt=query_prompt)
+        sql_chain = SQLDatabaseChain(
+            llm=llm, database=database, prompt=query_prompt, **kwargs
+        )
         decider_chain = LLMChain(
             llm=llm, prompt=decider_prompt, output_key="table_names"
         )