Skip to main content

​
Syntax

sequence.filter(predicate) → sequence

​
Arguments

List of arguments to provide.
​
predicate
function
required
A function that takes a document as input and returns a boolean value. Documents for which the predicate returns true will be included in the result.

​
Optargs

No optional arguments.

​
Returns

​
sequence
Cursor
Returns a cursor pointing to the filtered sequence of documents.

​
Behavior

  • The filter function evaluates the predicate for each document in the sequence.
  • Only documents for which the predicate returns true are included in the result.
  • The original sequence is not modified; a new filtered sequence is returned.
  • If no documents match the predicate, an empty sequence is returned.

​
Notes & Caveats

  • The predicate function can only have query builder expressions in its body.
  • The predicate function receives a single document parameter.
  • Use field to access specific fields within the document.
  • Complex predicates can be built using logical operators like and, or, and not.

​
Example

​
Filter users by age

Filter for users in the users table where the user’s age is greater than or equal to 21. 
await r
  .table('users')
  .filter((doc) => doc.age.ge(21))
  .run(client);

​
Filter with nested fields

Filter for orders where the shipping address country is UAE. 
await r
  .table('orders')
  .filter((doc) => doc.field('address.country').eq('UAE'))
  .run(client);

​
Filter with multiple conditions

Filter for orders where the status is shipped and the value is greater than 100. 
await r
  .table('orders')
  .filter((doc) => doc.status.eq('shipped').and(doc.value.gt(100)))
  .run(client);
  • eq - Logical Equality Operation
  • ne - Logical Inequality Operation
  • lt - Logical Less Than Operation
  • le - Logical Less Than or Equal Operation
  • gt - Logical Greater Than Operation
  • ge - Logical Greater Than or Equal Operation
  • and - Logical AND Operation
  • or - Logical OR Operation
  • not - Logical NOT Operation
  • field - Referencing a Field
  • table - Referencing a Table
Found a typo? Or maybe a broken link? RuloDB is open-source, help us fix it!