> ## Documentation Index
> Fetch the complete documentation index at: https://docs.prophecy.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Snowflake external table gem

> Read and write from Snowflake

export const execution_engine_0 = "Prophecy Automate"

<Info>This gem runs in {execution_engine_0}.</Info>

## Overview

The Snowflake Source and Target gems let you connect Prophecy pipelines to Snowflake tables for reading and writing data. This page outlines how to configure Snowflake sources and targets using the appropriate connections, locations, and properties.

## Create a Snowflake gem

To create a Snowflake Source or Target gem in your pipeline:

<Steps>
  <Step title="Add a Source or Target gem to the pipeline">
    1. Open your pipeline in the [Studio](/data-analysis/development/studio/studio).
    2. Click on **Source/Target** in the canvas.
    3. Select **Source** or **Target** from the dropdown.
    4. Click on the gem to open the configuration.
  </Step>

  <Step title="Select Snowflake format">
    In the **Type** tab, select **Snowflake**. Then, click **Next**.
  </Step>

  <Step title="Set location details">
    In the **Location** tab, set your connection details and table location. To learn more, jump to [Source location](#source-location) and [Target location](#target-location).
  </Step>

  <Step title="Set table properties">
    In the **Properties** tab, set the table properties. To learn more, jump to [Source
    properties](#source-properties) and [Target properties](#target-properties).
  </Step>

  <Step title="Preview data (Source only)">
    In the **Preview** tab, load a sample of the data and verify that it looks correct.
  </Step>
</Steps>

## Source configuration

Use these settings to configure a Snowflake Source gem for reading data.

### Source location

| Parameter                   | Description                                                                                                                      |
| --------------------------- | -------------------------------------------------------------------------------------------------------------------------------- |
| Format type                 | Table format for the source. For Snowflake tables, set to `snowflake`.                                                           |
| Select or create connection | Choose or create a [Snowflake connection](/data-analysis/environment/connections/snowflake) in the Prophecy fabric you will use. |
| Database                    | Snowflake database containing the table you want to read from.                                                                   |
| Schema                      | Schema within the database where the table is located.                                                                           |
| Name                        | Exact name of the Snowflake table to read data from.                                                                             |

### Source properties

Infer or manually configure the schema of your Source gem. Optionally, add a description for your table. Additional properties are not supported at this time.

## Target configuration

Use these settings to configure a Snowflake Target gem for writing data.

### Target location

| Parameter                   | Description                                                                                                                      |
| --------------------------- | -------------------------------------------------------------------------------------------------------------------------------- |
| Format type                 | Table format for the target. For Snowflake tables, set to `snowflake`.                                                           |
| Select or create connection | Choose or create a [Snowflake connection](/data-analysis/environment/connections/snowflake) in the Prophecy fabric you will use. |
| Database                    | Snowflake database where the target table will be created or updated.                                                            |
| Schema                      | Schema within the database where the target table resides or will be created.                                                    |
| Name                        | Name of the Snowflake table to write data to. If the table doesn't exist, it will be created automatically.                      |

### Target properties

| Property    | Description                                                                                                     | Default |
| ----------- | --------------------------------------------------------------------------------------------------------------- | ------- |
| Description | Description of the table.                                                                                       | None    |
| Write Mode  | Whether to overwrite the table completely, append new data to the table, or throw an error if the table exists. | None    |