@brobridge/atomic-informix 0.0.11

Informix database module for Brobridge Atomic

npm install @brobridge/atomic-informix

atomic-informix

Informix Database Module for Brobridge Atomic (Compatible with Node-RED).

Overview

@brobridge/atomic-informix is an Informix database module designed specifically for Atomic, fully compatible with the Node-RED development environment. It provides main nodes:

• Informix Connection: Connection configuration and pool manager
• Informix Execute: Query execution with streaming support
• Flow Control: Control flow node for streaming data (requires @brobridge/atomic-flowcontrol)

Installation

npm install @brobridge/atomic-informix

For flow control functionality, also install:

npm install @brobridge/atomic-flowcontrol

Features

• Efficient connection management with IBM DB2 driver
• Static or dynamic SQL execution via msg.query
• Delivery options:
  • direct: returns all results at once
  • streaming: sends rows in batches using Informix queryStream API
• SQL Playground UI to test queries interactively
• Supports continue and break controls for streaming sessions (with Flow Control node)
• Memory-efficient streaming that doesn't load entire result sets into memory

Nodes

Informix Connection

Manages database configuration and connection settings.

• Required fields: server, port, database, username, password
• Secure connection management with connection pooling

Informix Execute

Executes SQL queries with flexible query sources and delivery modes.

• Query Source:
  • auto: Uses embedded SQL command
  • dynamic: Uses msg.query as input
• Delivery Mode:
  • direct: Entire result set is returned
  • streaming: Sends rows in batches with session control using conn.queryStream()
• Output:
  • Output to msg.payload or custom property
• SQL Playground for testing queries interactively in the editor

Flow Control

Controls flow when using streaming mode in Informix Execute node.

• continue: Resume the session
• break: Cancel the session
• Supports targeting specific Execute nodes

Note: Flow Control functionality requires the @brobridge/atomic-flowcontrol package.

Streaming Mode

The streaming mode uses Informix's native queryStream() API to efficiently process large datasets:

const stream = conn.queryStream(sql, parameters);
stream.on('data', (row) => {
    // Process row by row without loading entire result set
});

This approach:

• Prevents memory overflow with large datasets
• Provides real-time data processing
• Allows flow control to pause/resume streams
• Maintains safe connection handling

Example Flow: Streaming Data Processing

The streaming mode allows you to process large datasets in batches:

1. Configure Informix Execute node with streaming delivery method
2. Set appropriate batch size (Max Records)
3. Use Flow Control node to manage stream processing
4. Implement your data processing logic between batches

Variable Substitution

SQL queries support variable substitution using template literals:

SELECT * FROM users WHERE id = ${msg.payload.userId}

Flow Control Usage

When using streaming mode:

1. Set Informix Execute node to "Streaming" delivery method
2. Connect your processing logic after the Informix Execute node
3. Add a Flow Control node to continue or break the stream
4. Configure the Flow Control node to target your Informix Execute node

Example message structure for streaming:

{
  payload: {
    results: [...],      // Batch of rows
    rowsAffected: 100,   // Number of rows in this batch
    complete: false      // false for batches, true for final batch
  }
}

Dependencies

• Node.js >= 18
• Node-RED >= 2.0.0
• IBM DB2 Driver (ibm_db)
• @brobridge/atomic-sdk for flow control functionality

License

Licensed under the Apache License

Authors

Copyright(c) 2023 Fred Chien <[email protected]>