feat: Snowflake integration (#268)

* add md

* Update integrations/snowflake.md

---------

Co-authored-by: Tuana Çelik <[email protected]>

integrations/snowflake.md

@@ -0,0 +1,116 @@
+---
+layout: integration
+name: Snowflake
+description: A Snowflake integration that allows table retrieval from a Snowflake database.
+authors:
+  - name: Mohamed Sriha
+    socials:
+      github: medsriha
+  - name: deepset
+    socials:
+      github: deepset-ai
+      twitter: deepset_ai
+      linkedin: deepset-ai
+pypi: https://pypi.org/project/snowflake-haystack
+repo: https://github.com/deepset-ai/haystack-core-integrations/tree/main/integrations/snowflake
+report_issue: https://github.com/deepset-ai/haystack-core-integrations/issues
+type: Data Ingestion
+logo: /logos/snowflake.png
+version: Haystack 2.0
+---
+
+[![PyPI - Version](https://img.shields.io/pypi/v/snowflake-haystack.svg)](https://pypi.org/project/snowflake-haystack)
+[![PyPI - Python Version](https://img.shields.io/pypi/pyversions/snowflake-haystack.svg)](https://pypi.org/project/snowflake-haystack)
+-----
+
+**Table of Contents**
+
+- [Snowflake table retriever for Haystack](#snowfkale-table-retriever-for-haystack)
+  - [Installation](#installation)
+  - [Usage](#usage)
+  - [Examples](#examples)
+  - [License](#license)
+
+## Installation
+Use `pip` to install Snowflake:
+
+```console
+pip install snowflake-haystack
+```
+## Usage
+Once installed, initialize the `SnowflakeTableRetriever` to use it with Haystack 2.0:
+
+```python
+from haystack_integrations.components.retrievers.snowflake import SnowflakeTableRetriever
+
+# Provide your Snowflake credentials during intialization.
+executor = SnowflakeTableRetriever(
+    user="<ACCOUNT-USER>",
+    account="<ACCOUNT-IDENTIFIER>",
+    api_key=Secret.from_env_var("SNOWFLAKE_API_KEY"),
+    warehouse="<WAREHOUSE-NAME>",
+)
+```
+
+Ensure you have `select` access to the tables before querying the database. More details [here](https://docs.snowflake.com/en/user-guide/security-access-control-privileges):
+```python
+response = executor.run(query="""select * from database_name.schema_name.table_name""")
+```
+During component initialization, you could provide the schema and database name to avoid needing to provide them in the SQL query:
+```python
+executor = SnowflakeTableRetriever(
+    ...
+    schema_name="<SCHEMA-NAME>",
+    database ="<DB-NAME>"
+)
+
+response = executor.run(query="""select * from table_name""")
+```
+Snowflake table retriever returns a Pandas dataframe and a Markdown version of the table:
+```python
+
+print(response["dataframe"].head(2))  # Pandas dataframe
+#   Column 1  Column 2
+# 0       Value1 Value2
+# 1       Value1 Value2
+
+print(response["table"])  # Markdown
+# | Column 1  | Column 2  |
+# |:----------|:----------|
+# | Value1    | Value2    |
+# | Value1    | Value2    |
+```
+
+Using `SnowflakeTableRetriever` within a pipeline:
+
+```python
+from haystack import Pipeline
+from haystack.utils import Secret
+from haystack.components.builders import PromptBuilder
+from haystack.components.generators import OpenAIGenerator
+from haystack_integrations.components.retrievers.snowflake import SnowflakeTableRetriever
+
+executor = SnowflakeTableRetriever(
+    user="<ACCOUNT-USER>",
+    account="<ACCOUNT-IDENTIFIER>",
+    api_key=Secret.from_env_var("SNOWFLAKE_API_KEY"),
+    warehouse="<WAREHOUSE-NAME>",
+)
+
+pipeline = Pipeline()
+pipeline.add_component("builder", PromptBuilder(template="Describe this table: {{ table }}"))
+pipeline.add_component("snowflake", executor)
+pipeline.add_component("llm", OpenAIGenerator(model="gpt-4o"))
+
+pipeline.connect("snowflake.table", "builder.table")
+pipeline.connect("builder", "llm")
+
+pipeline.run(data={"query": "select employee, salary from table limit 10;"})
+```
+
+## Examples
+You can find a code example showing how to use the Snowflake Retriever under the `example/` folder of [this repo](https://github.com/deepset-ai/haystack-core-integrations/tree/main/integrations/snowflake).
+
+## License
+
+`snowflake-haystack` is distributed under the terms of the [Apache-2.0](https://spdx.org/licenses/Apache-2.0.html) license.