Describe the problem/error/question
Hello dear community,
I’m running into a strange issue with one of my n8n workflows that processes a large database (around 50,000 records). The general logic looks like this:
-
The workflow starts by fetching the total count of records and setting a counter to zero.
-
It then enters a loop that fetches data from the database in batches.
-
After each batch, it checks whether more than one item was returned:
-
If yes → continue the cycle.
-
If no → stop the loop, write a timestamp (marking the sync as finished), and end successfully.
-
Everything works as expected for most of the process — all 50,000 items are fetched and processed correctly — but when it reaches the last cycle, where only one record should remain and the “stop” branch should trigger, it doesn’t.
Instead:
-
The condition (if > 1) never seems to behave correctly.
-
The workflow just loops again and gets stuck, sometimes indefinitely.
-
There are no visible errors in the execution logs or console, even though the process eventually crashes or times out.
-
The MySQL node often shows as “running” when the whole process stalls.
I’ve tried debugging with manual runs and inspecting the execution data, but can’t find why the condition never evaluates properly or why it doesn’t exit cleanly after the last cycle. And there are no errors in the console.
What I’ve checked:
-
The “If” node logic (looks correct: should trigger failure path when items <= 1).
-
No unhandled errors or exceptions appear in logs.
-
MySQL query executes fine when tested independently.
Question:
Has anyone seen similar behavior where a looping workflow in n8n:
-
Never exits a conditional branch even when the condition should evaluate to false, and
-
Gets stuck in execution without logging any error?
Could it be related to how n8n handles array lengths or item counts in an If node, or possibly something about how MySQL returns the final “one-row” result?
Any insights or debugging ideas would be hugely appreciated 
Please share your workflow
{
"nodes": [
{
"parameters": {
"operation": "upsert",
"schema": {
"__rl": true,
"value": "public",
"mode": "list",
"cachedResultName": "public"
},
"table": {
"__rl": true,
"value": "ProdReplica",
"mode": "list",
"cachedResultName": "ProdReplica"
},
"columns": {
"mappingMode": "defineBelow",
"value": {
"student_id": "={{ $('fetchProd').item.json.student_id }}",
},
"matchingColumns": [
"uniq_quiz"
],
"schema": [
{
"id": "uniq_quiz",
"displayName": "uniq_quiz",
"required": true,
"defaultMatch": false,
"display": true,
"type": "string",
"canBeUsedToMatch": true,
"removed": false
},
],
"attemptToConvertTypes": false,
"convertFieldsToString": false
},
"options": {}
},
"type": "n8n-nodes-base.postgres",
"typeVersion": 2.6,
"position": [
432,
0
],
"id": "81e4cafb-da34-4158-a45c-bc450923f137",
"name": "Insert or update rows in a table",
"credentials": {
"postgres": {
"id": "X3LY7hQdwbagmauR",
"name": "Postgres account"
}
}
},
{
"parameters": {
"conditions": {
"options": {
"caseSensitive": true,
"leftValue": "",
"typeValidation": "loose",
"version": 2
},
"conditions": [
{
"id": "0a9c85e2-0301-4e4a-9e5f-5f9b1b70efe9",
"leftValue": "={{ $('fetchProd').all().length }}",
"rightValue": "=1",
"operator": {
"type": "number",
"operation": "gt"
}
}
],
"combinator": "and"
},
"looseTypeValidation": true,
"options": {}
},
"type": "n8n-nodes-base.if",
"typeVersion": 2.2,
"position": [
832,
48
],
"id": "22cec9e5-eb40-47ff-9746-d591594012b5",
"name": "If"
},
{
"parameters": {
"path": "replicateDb",
"options": {}
},
"type": "n8n-nodes-base.webhook",
"typeVersion": 2.1,
"position": [
-672,
80
],
"id": "c3dff0e3-a33a-4780-94e8-07b90cf2db53",
"name": "Webhook",
"webhookId": "e0b711c7-5564-4217-b353-a73060cd5be2"
},
{
"parameters": {
"operation": "executeQuery",
"query": "UPDATE meta\nSET latest_quiz_id = latest_quiz_id + 5000\nWHERE id = 1\nRETURNING latest_quiz_id;",
"options": {}
},
"type": "n8n-nodes-base.postgres",
"typeVersion": 2.6,
"position": [
656,
0
],
"id": "f6108411-1b4d-4592-b660-619c3718b3a1",
"name": "set counter ++",
"executeOnce": true,
"credentials": {
"postgres": {
"id": "X3LY7hQdwbagmauR",
"name": "Postgres account"
}
}
},
{
"parameters": {
"operation": "executeQuery",
"query": "SELECT\n q.*,\n s.*,\n sc.*\nFROM quizes AS q\nLEFT JOIN students AS s\n ON s.id = q.student_id\nLEFT JOIN schools AS sc\n ON sc.id = s.school_id\nWHERE q.id > {{ $('getCurrLastQuiz').item.json.latest_quiz_id }}\nORDER BY q.id ASC\nLIMIT 5000",
"options": {}
},
"type": "n8n-nodes-base.mySql",
"typeVersion": 2.5,
"position": [
0,
0
],
"id": "8a703b30-2905-4cc1-ac7f-ab8ea785681c",
"name": "fetchProd",
"credentials": {
"mySql": {
"id": "PJLmOunJDKBtGQeN",
"name": "MySQL account"
}
}
},
{
"parameters": {
"operation": "executeQuery",
"query": "SELECT latest_quiz_id FROM meta WHERE id = 1;",
"options": {}
},
"type": "n8n-nodes-base.postgres",
"typeVersion": 2.6,
"position": [
-224,
80
],
"id": "a225855e-a406-4a67-8b53-af0e297703d7",
"name": "getCurrLastQuiz",
"alwaysOutputData": false,
"credentials": {
"postgres": {
"id": "X3LY7hQdwbagmauR",
"name": "Postgres account"
}
}
},
{
"parameters": {
"operation": "executeQuery",
"query": "UPDATE meta\nSET latest_quiz_id = 0\nWHERE id = 1;",
"options": {}
},
"type": "n8n-nodes-base.postgres",
"typeVersion": 2.6,
"position": [
-448,
80
],
"id": "aa073480-5c07-45a6-b619-fd05b755e90d",
"name": "reset",
"credentials": {
"postgres": {
"id": "X3LY7hQdwbagmauR",
"name": "Postgres account"
}
}
},
{
"parameters": {
"operation": "update",
"schema": {
"__rl": true,
"mode": "list",
"value": "public"
},
"table": {
"__rl": true,
"value": "meta",
"mode": "list",
"cachedResultName": "meta"
},
"columns": {
"mappingMode": "defineBelow",
"value": {
"id": 1,
"last_update": "={{ new Date().toISOString() }}"
},
"matchingColumns": [
"id"
],
"schema": [
{
"id": "latest_quiz_id",
"displayName": "latest_quiz_id",
"required": false,
"defaultMatch": false,
"display": true,
"type": "number",
"canBeUsedToMatch": true,
"removed": true
},
{
"id": "id",
"displayName": "id",
"required": false,
"defaultMatch": true,
"display": true,
"type": "number",
"canBeUsedToMatch": true,
"removed": false
},
{
"id": "last_update",
"displayName": "last_update",
"required": false,
"defaultMatch": false,
"display": true,
"type": "dateTime",
"canBeUsedToMatch": true
}
],
"attemptToConvertTypes": false,
"convertFieldsToString": false
},
"options": {}
},
"type": "n8n-nodes-base.postgres",
"typeVersion": 2.6,
"position": [
1136,
64
],
"id": "c2952736-d5d8-4e04-a315-86202005ab0a",
"name": "set time",
"executeOnce": true,
"alwaysOutputData": true,
"credentials": {
"postgres": {
"id": "X3LY7hQdwbagmauR",
"name": "Postgres account"
}
}
},
{
"parameters": {REMOVED PRIVATE},
"type": "n8n-nodes-base.set",
"typeVersion": 3.4,
"position": [
208,
0
],
"id": "e592173a-2c47-483d-806e-e835eec2ec99",
"name": "Edit fields"
}
],
"connections": {
"Insert or update rows in a table": {
"main": [
[
{
"node": "set counter ++",
"type": "main",
"index": 0
}
]
]
},
"If": {
"main": [
[
{
"node": "getCurrLastQuiz",
"type": "main",
"index": 0
}
],
[
{
"node": "set time",
"type": "main",
"index": 0
}
]
]
},
"Webhook": {
"main": [
[
{
"node": "reset",
"type": "main",
"index": 0
}
]
]
},
"set counter ++": {
"main": [
[
{
"node": "If",
"type": "main",
"index": 0
}
]
]
},
"fetchProd": {
"main": [
[
{
"node": "Edit fields",
"type": "main",
"index": 0
}
]
]
},
"getCurrLastQuiz": {
"main": [
[
{
"node": "fetchProd",
"type": "main",
"index": 0
}
]
]
},
"reset": {
"main": [
[
{
"node": "getCurrLastQuiz",
"type": "main",
"index": 0
}
]
]
},
"set time": {
"main": [
[]
]
},
"Edit fields": {
"main": [
[
{
"node": "Insert or update rows in a table",
"type": "main",
"index": 0
}
]
]
}
},
"pinData": {},
"meta": {
"instanceId": "a1e8e16e8251d7e450a77c833c5134c5211d75fa49c6fd2e71206b45ffe53bfb"
}
}
Share the output returned by the last node
N/A
Information on your n8n setup
- n8n version:Self-hosted
- Database (default: SQLite): Postgres
- n8n EXECUTIONS_PROCESS setting (default: own, main): main
- Running n8n via (Docker, npm, n8n cloud, desktop app): docker
- Operating system:linux
