> For the complete documentation index, see [llms.txt](https://docs.bdb.ai/data-pipeline-6/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bdb.ai/data-pipeline-6/components/writers/db-writer.md).

# DB Writer

The DB writer is a spark-based writer component which gives you capability to write data to multiple database sources.

All component configurations are classified broadly into the following sections:

* ​[​Basic Information​](/data-pipeline-6/components/component-base-configuration.md)​
* Meta Information
* ​[Resource Configuration​](/data-pipeline-6/components/resource-configuration.md)​
* ​[Connection Validation](https://docs.bdb.ai/7.6/data-pipeline/components/connection-validation)​

{% hint style="success" %}
*Please check out the given demonstration to configure the component.*
{% endhint %}

{% embed url="<https://files.gitbook.com/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fc39ZvXI46qjXzpN3rYAg%2Fuploads%2FgBcXWWdOXknp0JN4cgtZ%2F2023-10-30-18-01-35%20(online-video-cutter.com).mp4?alt=media&token=89aa1f64-b6f6-40da-a31a-19c12024a58a>" %}
***DB Writer configuration for ClickHouse Driver***
{% endembed %}

{% embed url="<https://files.gitbook.com/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fc39ZvXI46qjXzpN3rYAg%2Fuploads%2FdSepVFheAHDMQ3matHLz%2F2023-09-04-18-46-34%20(online-video-cutter.com).mp4?alt=media&token=d3074c8c-2f23-4cc6-b81f-7a3137a59868>" %}
***Configuring DB Writer component for Redshift Driver***
{% endembed %}

### **Drivers Available**

<details>

<summary>Supported Drivers</summary>

* MySQL
* Oracle
* PostgreSQL
* MS-SQL
* ClickHouse
* Snowflake
* Redshift

</details>

{% hint style="warning" %}
*<mark style="color:green;">**Please Note:**</mark>*&#x20;

* *The **ClickHouse** driver in the **Spark** components will use the **HTTP Port** and not the **TCP** port.*
* *It is always recommended to create the table before activating the pipeline to avoid errors as RDBMS has a strict schema and can result in errors.*
* When using the ***Redshift*** driver with a ***Boolean*** datatype in JDBC, the table is not created unless you pass the create table query.\
  Alternatively, you can use a column filter to convert a ***Boolean*** value to a ***String*** for the desired operation.
  {% endhint %}

### Configuring the Meta Information of Azure Writer

* **Database name:** Enter the Database name.
* **Table name:** Provide a table name where the data has to be written.
* **Enable SSL:** Check this box to enable SSL for this components. Enable SSL feature in DB reader component will  appear only for three(3) drivers: ***MongoDB, PostgreSQL and ClickHouse***.
* **Certificate Folder:** This option will appear when the Enable SSL field is checked-in. The user has to select the certificate folder from drop down which contains the files which has been uploaded to the admin settings. Please refer the below given images for the reference.
* **Schema File Name:** Upload a Spark schema file of the data which has to be written in JSON format.
* **Save Mode**: Select the save mode from the drop-down menu:
  * **Append**: It will append the data in the table.
  * **Overwrite**: It will overwrite the data in the table.
  * **Upsert:** This operation allows the users to insert a new record or update existing data into a table. For configuring this, we need to provide the Composite Key.
    * **Sort Column:** This field will appear only when ***Upsert*** is selected as ***Save mode***. If there are multiple records with the same composite key but different values in the batch, the system identifies the record with the latest value based on the Sort column. The Sort column defines the ordering of records, and the record with the highest value in the sort column is considered the latest.
  * **Column Filter**: Enter the column names here. Only the specified columns will be fetched from the data from the previous connected event to the DB Writer. In this field, the user needs to fill in the following information:
    * **Name**: Enter the name of the column which has to be written from the previous event. The user can add multiple columns by clicking on the ***"Add New Column"*** option.
    * **Alias**: Enter the alias name for the selected column name.
    * **Column Type**: Enter the data type of the column.
    * **Upload**: This option allows the user to upload a data file in CSV, JSON, or EXCEL format. The column names will be automatically fetched from the uploaded data file and filled out in the Name, Alias, and Column Type fields.
    * **Download Data**: This option will download the data filled in the Column Filter field in JSON format.
    * **Delete Data**: This option will clear all the information filled in the Column Filter field.
  * ***Query:*** In this field, we can write a DDL for creating the table in database where the in-event data has to be written. For example, please refer the below image:

<figure><img src="https://content.gitbook.com/content/wT6nkX9iZNRiZKBnpFmn/blobs/I9LSOWuPvTQeguCCT2wD/image.png" alt=""><figcaption><p><em><strong>Writing a DDL for creating a table in DB.</strong></em></p></figcaption></figure>

<figure><img src="https://content.gitbook.com/content/wT6nkX9iZNRiZKBnpFmn/blobs/nzByZc12Ajq2hsrsrASH/image.png" alt=""><figcaption><p><em><strong>Sort Column in Upsert Mode for DB Writer (ClickHouse driver)</strong></em></p></figcaption></figure>

<figure><img src="https://content.gitbook.com/content/wT6nkX9iZNRiZKBnpFmn/blobs/BOCWJR7gDb0pwYkTEnq4/image.png" alt=""><figcaption><p><em><strong>Meta Information fields of the DB writer (with SSL enabled)</strong></em> </p></figcaption></figure>

{% hint style="warning" %}
*<mark style="color:green;">Please Note:</mark>*&#x20;

* *In **DB Writer** component, the Save Mode for ClickHouse driver is as follows:*
  * ***Append**: It will create a table in ClickHouse database with a table engine **StripeLog**.*
  * ***Upsert**: It will create a table in ClickHouse database with a table engine **ReplacingMergeTree**.*
* *If the user is using **Append** as the Save mode in **ClickHouse Writer (Docker component)** and **Data Sync (ClickHouse driver)**, it will create a table in the ClickHouse database with a table engine **Memory**.*
* Currently, the ***Sort column*** field is only available for the following drivers in the DB Writer: ***MSSQL**, **PostgreSQL**, **Oracle**, **Snowflake**, and **ClickHouse.***&#x20;
  {% endhint %}