Snowflake Upgrade & Migration

# Check Node.js driver changelog
open https://github.com/snowflakedb/snowflake-connector-nodejs/blob/master/CHANGELOG.md

# Check Python connector changelog
open https://docs.snowflake.com/en/release-notes/clients-drivers/python-connector-2025

# Check Snowflake BCR (Behavior Change Releases)
open https://docs.snowflake.com/en/release-notes/bcr-bundles

Step 3: Upgrade on a Branch

# Node.js
git checkout -b chore/upgrade-snowflake-sdk
npm install snowflake-sdk@latest
npm test

# Python
git checkout -b chore/upgrade-snowflake-connector
pip install --upgrade snowflake-connector-python
pytest

Step 4: Handle Common Breaking Changes

Node.js Driver Changes (1.x to 2.x+):

// Old: Synchronous configure
// snowflake.configure({ logLevel: 'DEBUG' });

// New: Same API but check for removed options
import snowflake from 'snowflake-sdk';
snowflake.configure({
  logLevel: process.env.NODE_ENV === 'development' ? 'DEBUG' : 'WARN',
  // insecureConnect removed in newer versions — use proper certs
});

// connectAsync added in later versions
const conn = snowflake.createConnection({ /* ... */ });
await conn.connectAsync();  // Promise-based (if available)
// Fallback for older versions:
await new Promise((resolve, reject) => {
  conn.connect((err, c) => err ? reject(err) : resolve(c));
});

Python Connector Changes:

# v3.x: fetch_pandas_all() requires pandas extra
# pip install "snowflake-connector-python[pandas]"

# v3.x: write_pandas() moved to snowflake.connector.pandas_tools
from snowflake.connector.pandas_tools import write_pandas

# v2.x to v3.x: DictCursor import changed
# Old: from snowflake.connector import DictCursor
# New:
cursor = conn.cursor(snowflake.connector.DictCursor)

# Arrow result format (default in newer versions)
conn = snowflake.connector.connect(
    # ...
    arrow_number_to_decimal=True,  # New in 3.x
)

Snowflake Platform BCR (Behavior Change Releases):

-- Check which BCR bundles are enabled
SELECT SYSTEM$SHOW_ACTIVE_BEHAVIOR_CHANGE_BUNDLES();

-- Test a specific BCR before it's mandatory
ALTER ACCOUNT SET BCR_ENABLED = '2024_08';

-- Common BCRs to watch:
-- Stricter type checking in COPY INTO
-- Changed NULL handling in aggregations
-- Modified INFORMATION_SCHEMA view columns

Step 5: Validate After Upgrade

// src/tests/integration/upgrade-validation.test.ts
describe('Post-upgrade validation', () => {
  it('should connect with existing credentials', async () => {
    const conn = createConnection();
    await connectAsync(conn);
    expect(conn.getId()).toBeTruthy();
  });

  it('should execute parameterized queries', async () => {
    const rows = await query(conn,
      'SELECT ? AS test_value', [42]
    );
    expect(rows[0].TEST_VALUE).toBe(42);
  });

  it('should stream large results', async () => {
    let count = 0;
    for await (const row of streamQuery(conn,
      'SELECT SEQ4() AS n FROM TABLE(GENERATOR(ROWCOUNT => 10000))'
    )) {
      count++;
    }
    expect(count).toBe(10000);
  });

  it('should handle errors correctly', async () => {
    await expect(
      query(conn, 'SELECT * FROM nonexistent_table_xyz')
    ).rejects.toThrow(/does not exist/);
  });
});

Step 6: Rollback Procedure

# Node.js — pin exact version
npm install [email protected] --save-exact

# Python — pin exact version
pip install snowflake-connector-python==3.6.0

# Git rollback
git checkout main -- package-lock.json package.json
npm ci

Error Handling

Resources

• Node.js Driver Releases
• Python Connector Release Notes
• Behavior Change Bundles

Next Steps

For CI integration during upgrades, see snowflake-ci-integration.