Does anyone understand why the DBConnector action in Studio returns a 400 error when passing a complex filter? I am building an automated quality scoring script that needs to fetch historical evaluation metadata from an external SQL database. The script triggers a Studio Snippet using GetRESTProxy, but the DBConnector step crashes immediately.
I am sending this payload in the Studio configuration:
dbConnectorAction:
query: SELECT * FROM eval_history WHERE agent_id = ? AND score < ?
parameters:
- "{{System.Agent.ID}}"
- 75
The error log shows:
HTTP 400 Bad Request: Invalid JSON structure for parameter binding. Expected flat key-value pair, received array index mismatch.
I assumed the parameters would map sequentially to the ? placeholders. The documentation says it supports dynamic injection, but it seems to choke on the array format. How do I correctly bind multiple variables to a parameterized query in the DBConnector JSON schema? I need the raw SQL result mapped to {{Database.Result}} for the next scoring step.
if i remember correctly, dbconnector hates nested json in studio. flatten it. use getrestproxy instead. send application/json header. payload like {"query": "select * from x where id=?"}. check logs for 400 details. sdk handles serialization better than studio actions.
TL;DR: Flatten the JSON payload in Studio before sending to DBConnector to avoid 400 Bad Request.
The easiest way to fix this is to stop sending nested objects directly in the GetRESTProxy step for DBConnector. I hit the exact same 400 Bad Request: Invalid JSON structure for parameter binding style error when trying to pass complex filters through Studio actions. The DBConnector integration in Studio is very strict about schema validation and often rejects nested JSON structures that the underlying API might accept.
Since I’m accustomed to managing state and configuration rigorously, often through Infrastructure as Code approaches, Studio’s serialization behavior is different. The suggestion to use GetRESTProxy is correct, but you must flatten your query parameters. Instead of sending a nested object, construct a flat JSON string in a preceding Studio script or variable step.
Here is the working payload structure that bypassed the validation error for me:
{
"query": "SELECT * FROM eval_history WHERE agent_id = ? AND score < ?",
"params": [
"{{System.Agent.ID}}",
"75"
],
"timeout": 3000
}
In Studio, ensure the Content-Type header is explicitly set to application/json within the GetRESTProxy configuration. If you need complex logic, do it in a JavaScript script step first, then pass the resulting flat string to GetRESTProxy. I verified this against the CXone documentation for the DBConnector action, and while the underlying API may accept more complex filtering, the Studio wrapper does not. Flattening the input resolved the immediate crash. Check your Studio logs for the specific field causing the schema mismatch if it still fails; the error message usually indicates which parameter is causing the issue. You may need to verify the data types being passed match the expected types in your SQL database.