Advanced Filtering

Kassie supports CQL WHERE clauses for filtering table data. This guide covers common filter patterns and operators.

Using the Filter Bar

TUI

Press / to open the filter bar, type your WHERE clause, and press Enter to apply.

Press Esc to cancel, or clear the filter bar and press Enter to remove the filter.

Web

The filter bar sits above the data grid. Type your WHERE clause and press Enter. Use the clear button (×) to remove the filter.

API

curl -s -X POST -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "keyspace": "app_data",
    "table": "users",
    "where_clause": "id = '\''550e8400-e29b-41d4-a716-446655440000'\''",
    "page_size": 100
  }' \
  http://localhost:8080/api/v1/data/filter | jq

Filter by Partition Key

The most common and efficient filter — queries a single partition:

id = '550e8400-e29b-41d4-a716-446655440000'

TIP

Filtering by partition key is always fast because Cassandra routes directly to the responsible node.

Filter by Clustering Key

Filter within a partition using clustering columns:

id = '550e8400-...' AND created_at > '2024-01-01'

id = '550e8400-...' AND created_at >= '2024-01-01' AND created_at < '2024-02-01'

WARNING

Clustering key filters require the partition key to be specified. Filtering by clustering columns only will fail.

Comparison Operators

Operator	Example	Notes
=	status = 'active'	Exact match
<	age < 30	Less than
>	score > 100	Greater than
<=	created_at <= '2024-12-31'	Less than or equal
>=	priority >= 5	Greater than or equal

Using the IN Operator

Query multiple partition key values:

id IN ('550e8400-...', '6ba7b810-...', '7c9e6679-...')

TIP

IN on the partition key sends parallel queries to different nodes — very efficient for small lists.

Using CONTAINS

Filter collections (lists, sets, maps):

tags CONTAINS 'urgent'

properties CONTAINS KEY 'color'

WARNING

CONTAINS queries may require ALLOW FILTERING and can be slow on large datasets. Cassandra may reject these queries if it estimates a full table scan is needed.

Combining Filters

Combine multiple conditions with AND:

user_id = '550e8400-...' AND status = 'active' AND created_at > '2024-01-01'

WARNING

Cassandra has strict rules about which columns can be filtered together. Generally:

• Partition key columns must be specified with = or IN
• Clustering columns must follow the clustering order
• Non-key columns may require secondary indexes

Common Filter Examples

Users table

-- Find a specific user
id = '550e8400-e29b-41d4-a716-446655440000'

-- Find users created in 2024
id = '550e8400-...' AND created_at >= '2024-01-01' AND created_at < '2025-01-01'

Orders table

-- Find orders for a customer
customer_id = '6ba7b810-9dad-11d1-80b4-00c04fd430c8'

-- Find recent orders
customer_id = '6ba7b810-...' AND order_date > '2024-06-01'

Logs table

-- Find errors for a service
service = 'payment-service' AND level = 'ERROR'

-- Find logs in a time range
service = 'api-gateway' AND timestamp >= '2024-06-15T00:00:00Z' AND timestamp < '2024-06-16T00:00:00Z'

Filter Validation

Kassie validates filter syntax before sending to the database:

Error	Cause	Fix
Syntax error	Invalid CQL syntax	Check quotes and operators
Missing partition key	Non-key filter without PK	Add partition key condition
Invalid column name	Column doesn't exist	Check table schema
Type mismatch	Wrong value type for column	Match value type to column type

Validation errors are displayed inline in the filter bar (both TUI and Web).

Tips

1. Always start with the partition key — it's the most efficient filter
2. Use the inspector to check column types before writing filters
3. Quote string values — name = 'Alice' not name = Alice
4. UUID values need quotes — id = '550e8400-...'
5. Timestamps use ISO 8601 — created_at > '2024-01-01T00:00:00Z'
6. Clear the filter to return to unfiltered browsing