# Using Custom Filter Queries In MongoDB Actions
Using the Custom filter query field, you can filter the documents used in MongoDB actions in your recipes.
# Supported Actions
Custom filter queries are supported for the following MongoDB actions:
# How it works
Using MongoDB's Extended JSON (opens new window), you can construct queries that return a subset of documents from a collection.
Custom filter queries support:
# Using BSON Types
Custom filter queries accept BSON types (opens new window), with some limitations.
For example: This query would return documents with an ObjectId (oid) value of 5d505646cf6d4fe581014ab2:
{
   "_id":{
      "$oid":"5d505646cf6d4fe581014ab2"
   }
}
# Using JSON Types
Custom filter queries also accept JSON data types (opens new window) such as string, boolean, number, etc.
For example: The following query returns documents where the document's manager_id value is a string type:
{
   "manager_id":"string"
}
# Using Query Operators
You can also use query operators (opens new window) to perform comparison and logic operations. Note: There are some limitations on the operators that are currently supported.
For example: We'll use this query to search for documents in an employees collection:
{
   "manager_id":{
      "$oid":"5d505646cf6d4fe581014ab2"
   },
   "sales_closed":{
      "$gt":{
         "$numberDecimal":"1000000"
      }
   },
   "date_hired":{
      "$gt":{
         "$date":"2020-12-31T00:00:00.000Z"
      }
   }
}
The above query searches for documents - or employees - that:
- Have a manager_idvalue of5d505646cf6d4fe581014ab2)
- Have a total sales_closedvalue greater than$1,000,000, and
- Were hired after 2020-12-31(December 31, 2020)
# Limitations
- Only the following BSON types (opens new window) are currently supported: - Decimal128, synonymous with- $numberDecimal
- ObjectId, synonymous with- $oid
- Date, synonymous with- $date
 
- The $where(opens new window) query operator isn't currently supported
# Resources
 Last updated: 5/21/2025, 5:22:32 AM