Created fix for 5475
Currently in PGvector, we do not have any function that returns the
instance of an existing store. The from_documents always adds embeddings
and then returns the store. This fix is to add a function that will
return the instance of an existing store
Also changed the jupyter example for PGVector to show the example of
using the function
<!-- Remove if not applicable -->
Fixes # 5475
#### Before submitting
<!-- If you're adding a new integration, please include:
1. a test for the integration - favor unit tests that does not rely on
network access.
2. an example notebook showing its use
See contribution guidelines for more information on how to write tests,
lint
etc:
https://github.com/hwchase17/langchain/blob/master/.github/CONTRIBUTING.md
-->
#### Who can review?
@dev2049
@hwchase17
Tag maintainers/contributors who might be interested:
<!-- For a quicker response, figure out the right person to tag with @
@hwchase17 - project lead
Tracing / Callbacks
- @agola11
Async
- @agola11
DataLoaders
- @eyurtsev
Models
- @hwchase17
- @agola11
Agents / Tools / Toolkits
- @vowelparrot
VectorStores / Retrievers / Memory
- @dev2049
-->
---------
Co-authored-by: rajib76 <rajib76@yahoo.com>
Co-authored-by: Dev 2049 <dev.dev2049@gmail.com>
# Your PR Title (What it does)
Fixes the pgvector python example notebook : one of the variables was
not referencing anything
## Before submitting
## Who can review?
Community members can review the PR once tests pass. Tag
maintainers/contributors who might be interested:
VectorStores / Retrievers / Memory
- @dev2049
- Added links to the vectorstore providers
- Added installation code (it is not clear that we have to go to the
`LangChan Ecosystem` page to get installation instructions.)
