n8nworkflows.xyz/workflows/Create a table in Quest DB and insert data-592/readme-592.md

Create a table in Quest DB and insert data

https://n8nworkflows.xyz/workflows/create-a-table-in-quest-db-and-insert-data-592

Create a table in Quest DB and insert data

1. Workflow Overview

This workflow automates the process of creating a table in QuestDB and inserting data into it. It is designed for scenarios where a user wants to programmatically set up a new database table and populate it with initial data in QuestDB, a high-performance time series database. The workflow is divided into three logical blocks:

• 1.1 Input Trigger: Manual initiation of the workflow.
• 1.2 Table Creation: Executes a SQL query to create a new table in QuestDB.
• 1.3 Data Insertion: Prepares and inserts data rows into the newly created table.

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2. Block-by-Block Analysis

1.1 Input Trigger

• Overview:
  This block starts the workflow manually when a user clicks "execute." It allows manual testing and controlled initiation.

• Nodes Involved:

  • On clicking 'execute'

• Node Details:

  • On clicking 'execute'
    • Type: Manual Trigger
    • Configuration: No parameters; triggers workflow on manual execution.
    • Input: None
    • Output: Triggers downstream Query Execution node.
    • Failures: None anticipated; manual trigger.
    • Notes: Serves as the workflow entry point.

1.2 Table Creation

• Overview:
  Executes a SQL command to create a new table named test with two columns (id as integer, name as string) in QuestDB.

• Nodes Involved:

  • QuestDB (first instance)

• Node Details:

  • QuestDB
    • Type: QuestDB node for executing SQL queries
    • Configuration:
      • Operation: executeQuery
      • Query: CREATE TABLE test (id INT, name STRING);
      • Credentials: QuestDB credentials must be configured to connect to the database.
    • Input: Triggered by Manual Trigger node.
    • Output: Passes data to the Set node for data preparation.
    • Failures:
      • SQL syntax errors if table already exists or query malformed.
      • Connection/authentication issues with QuestDB credentials.
      • Timeout if QuestDB server is unresponsive.
    • Version Requirements: Compatible with n8n QuestDB node version 1.
    • Notes: Ensures table creation before data insertion.

1.3 Data Insertion

• Overview:
  Prepares a data record and inserts it into the previously created test table via QuestDB.

• Nodes Involved:

  • Set
  • QuestDB1 (second QuestDB node instance)

• Node Details:

  • Set

    • Type: Set node used to define the data payload
    • Configuration:
      • Sets two fields:
        • id (type: number) — no explicit value set (likely empty or to be dynamically set)
        • name (type: string) — fixed value "Tanay"
      • No additional options enabled.
    • Input: Receives trigger from previous QuestDB node after table creation.
    • Output: Provides structured data to QuestDB insertion node.
    • Failures: Potential empty or undefined id value if not set properly.
    • Notes: Prepares row data for insertion.

  • QuestDB1

    • Type: QuestDB node for inserting data
    • Configuration:
      • Operation: Default (implied insert based on parameters)
      • Table: test
      • Columns: id, name
      • Credentials: QuestDB credentials (same as first QuestDB node).
    • Input: Receives data from Set node.
    • Output: None (end of workflow)
    • Failures:
      • Data mismatch if id is undefined or invalid type.
      • Connection/authentication issues.
      • Table not existing if table creation failed.
    • Notes: Inserts the prepared data row into the test table.

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3. Summary Table

Node Name	Node Type	Functional Role	Input Node(s)	Output Node(s)	Sticky Note
On clicking 'execute'	Manual Trigger	Workflow start trigger	None	QuestDB
QuestDB	QuestDB (executeQuery)	Create test table	On clicking 'execute'	Set
Set	Set	Prepare data to insert	QuestDB	QuestDB1
QuestDB1	QuestDB	Insert data into table	Set	None

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4. Reproducing the Workflow from Scratch

1. Create Manual Trigger Node

   • Add a Manual Trigger node named On clicking 'execute'. No configuration needed.

2. Add QuestDB Node for Table Creation

   • Add a QuestDB node named QuestDB.
   • Set operation to executeQuery.
   • Enter SQL query: CREATE TABLE test (id INT, name STRING);
   • Configure QuestDB credentials (host, port, username, password).
   • Connect On clicking 'execute' node's output to this node's input.

3. Add Set Node to Prepare Data

   • Add a Set node named Set.
   • In Values to Set:
     • Add a Number field named id with no value preset (can be set dynamically or left empty).
     • Add a String field named name with value "Tanay".
   • Connect the output of QuestDB node to this node.

4. Add QuestDB Node for Data Insertion

   • Add another QuestDB node named QuestDB1.
   • Set operation to default or insert mode.
   • Set table to test.
   • Specify columns as id, name.
   • Use the same QuestDB credentials as before.
   • Connect Set node's output to this node.

5. Activate and Test Workflow

   • Save the workflow.
   • Execute the manual trigger node to run end-to-end: create table and insert data.

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5. General Notes & Resources

Note Content	Context or Link
QuestDB requires proper credentials and running instance to accept SQL queries and inserts.	Official QuestDB docs: https://questdb.io/docs/
The id field in the Set node is not preset; ensure to provide a valid number during runtime.	Workflow data preparation best practices