Chain for question-answering against an index.
Example
from langchain.llms import OpenAI
from langchain.chains import RetrievalQA
from langchain.faiss import FAISS
from langchain.vectorstores.base import VectorStoreRetriever
retriever = VectorStoreRetriever(vectorstore=FAISS(...))
retrievalQA = RetrievalQA.from_llm(llm=OpenAI(), retriever=retriever)
Validators
raise_deprecation » all fields
set_verbose » verbose
field retriever: BaseRetriever [Required]#
pydantic model langchain.chains.RetrievalQAWithSourcesChain[source]#
Question-answering with sources over an index.
Validators
raise_deprecation » all fields
set_verbose » verbose
validate_naming » all fields
field max_tokens_limit: int = 3375#
Restrict the docs to return from store based on tokens,
enforced only for StuffDocumentChain and if reduce_k_below_max_tokens is to true
field reduce_k_below_max_tokens: bool = False#
Reduce the number of results to return from store based on tokens limit
field retriever: langchain.schema.BaseRetriever [Required]#
Index to connect to.
pydantic model langchain.chains.SQLDatabaseChain[source]#
Chain for interacting with SQL Database.
Example
from langchain import SQLDatabaseChain, OpenAI, SQLDatabase
db = SQLDatabase(...)
db_chain = SQLDatabaseChain.from_llm(OpenAI(), db)
Validators
raise_deprecation » all fields
raise_deprecation » all fields
set_verbose » verbose
field database: SQLDatabase [Required]#
SQL Database to connect to.
field llm: Optional[BaseLanguageModel] = None#
[Deprecated] LLM wrapper to use.
rtdocs_stable/api.python.langchain.com/en/stable/reference/modules/chains.html