How to Store Workflow Data in n8n

1// Access global static data (shared across all nodes)
2const staticData = $getWorkflowStaticData('global');
3
4// Read a value (returns undefined if not set)
5const lastRunTime = staticData.lastRunTime;
6
7// Write a value (automatically saved after execution)
8staticData.lastRunTime = new Date().toISOString();
9staticData.runCount = (staticData.runCount || 0) + 1;
10
11return [{
12  json: {
13    lastRunTime: lastRunTime || 'First run',
14    currentRunTime: staticData.lastRunTime,
15    totalRuns: staticData.runCount
16  }
17}];

1// Code node: Track last processed ID for incremental sync
2const staticData = $getWorkflowStaticData('global');
3const lastProcessedId = staticData.lastProcessedId || 0;
4
5// Get all items from the previous node
6const items = $input.all();
7
8// Filter to only new items (ID greater than last processed)
9const newItems = items.filter(item => item.json.id > lastProcessedId);
10
11// Update the last processed ID
12if (newItems.length > 0) {
13  const maxId = Math.max(...newItems.map(item => item.json.id));
14  staticData.lastProcessedId = maxId;
15}
16
17return newItems.length > 0 ? newItems : [{
18  json: { message: 'No new items to process' }
19}];

1// Node-scoped static data — each node has its own storage
2const nodeData = $getWorkflowStaticData('node');
3
4// This 'counter' is independent from any other node's 'counter'
5nodeData.counter = (nodeData.counter || 0) + 1;
6nodeData.lastSeen = new Date().toISOString();
7
8return [{
9  json: {
10    nodeCounter: nodeData.counter,
11    nodeLastSeen: nodeData.lastSeen
12  }
13}];

1// Store complex data structures in static data
2const staticData = $getWorkflowStaticData('global');
3
4// Initialize a deduplication cache
5if (!staticData.processedEmails) {
6  staticData.processedEmails = {};
7}
8
9// Check and update the cache
10const items = $input.all();
11const newItems = [];
12
13for (const item of items) {
14  const email = item.json.email;
15  if (!staticData.processedEmails[email]) {
16    staticData.processedEmails[email] = {
17      firstSeen: new Date().toISOString(),
18      count: 1
19    };
20    newItems.push(item);
21  } else {
22    staticData.processedEmails[email].count += 1;
23  }
24}
25
26// Clean up old entries (keep only last 1000)
27const emails = Object.keys(staticData.processedEmails);
28if (emails.length > 1000) {
29  const toRemove = emails.slice(0, emails.length - 1000);
30  toRemove.forEach(e => delete staticData.processedEmails[e]);
31}
32
33return newItems.length > 0 ? newItems : [{ json: { message: 'All items already processed' } }];

1// PostgreSQL node configuration for storing workflow state
2// Operation: Execute Query
3// Query:
4
5-- Create a state table (run once)
6CREATE TABLE IF NOT EXISTS workflow_state (
7  workflow_id VARCHAR(50) PRIMARY KEY,
8  state_key VARCHAR(100) NOT NULL,
9  state_value JSONB NOT NULL,
10  updated_at TIMESTAMP DEFAULT NOW()
11);
12
13-- Upsert state data
14INSERT INTO workflow_state (workflow_id, state_key, state_value, updated_at)
15VALUES ('my-sync-workflow', 'last_cursor', '"abc123"'::jsonb, NOW())
16ON CONFLICT (workflow_id)
17DO UPDATE SET state_value = EXCLUDED.state_value, updated_at = NOW();
18
19-- Read state data
20SELECT state_value FROM workflow_state WHERE workflow_id = 'my-sync-workflow';