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Database scaling & optimization

Indexing, connection pooling, read replicas, query tuning, and throughput-aware SQL.

3 matches

How to Mock a Hot Shard Split in Python

Simulate a database hot shard splitting into two shards by key ranges when it exceeds a threshold, with a mock class for testing.

sharding databases mock

Python

import random
from collections import defaultdict


class HotShardMock:
    """Mock implementation of a hot shard split in a distributed database."""

    def __init__(self, shard_id="shard_1", max_entries=5):
        self.shard_id = shard_id
        self.max_entries = max_entries
        self.entries = {}

    def ad…

16 0 Open

Database scaling & optimization medium

Idempotent Writes for Sharded Databases in Python

Implement a mock shard with idempotent write support using request IDs to prevent duplicate writes and track the latest value per key.

idempotency sharding distributed-systems

Python

import json


class ShardMock:
    """Mock distributed shard with idempotent write support."""

    def __init__(self, shard_id):
        self.shard_id = shard_id
        self._store = {}

    def write(self, key, value, request_id):
        """Write value only if request_id not yet processed; idempotent."""
        i…

13 0 Open

Database scaling & optimization medium

Offset vs Keyset Pagination in Python

Demonstrate offset-based pagination and keyset (cursor) pagination with a simple in-memory dataset, showing how each returns pages of records.

pagination keyset offset

Python

"""Demonstrate pagination using offset vs keyset (cursor) approach."""

ITEMS = [
    {"id": 1, "name": "Alice"},
    {"id": 2, "name": "Bob"},
    {"id": 3, "name": "Carol"},
    {"id": 4, "name": "David"},
    {"id": 5, "name": "Eve"},
]

def offset_paginate(items, page, page_size):
    """Return a page using offset…

14 0 Open

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