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Database scaling & optimization

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

3 matches

How to Mock Sticky Session Read-Your-Writes in Python

Simulates a sticky session store that routes reads for a session to the node where the last write occurred, demonstrating read-your-writes consistency.

sticky sessions read-your-writes mock

Python

class StickySessionStore:
    def __init__(self):
        self.data = {}
        self.session_nodes = {}

    def write(self, session_id, key, value):
        self.data[key] = value
        self.session_nodes[session_id] = key
        return f"Wrote {key}={value} for session {session_id}"

    def read(self, session_i…

13 0 Open

Database scaling & optimization easy

How to mock directory-based sharding in Python

Simulates distributing files into logical shards using a deterministic hash of each filename, mocking how a database might shard rows across nodes.

sharding hash partitioning

Python

import os
import hashlib
from collections import defaultdict
from pathlib import Path


def get_shard_for_key(key: str, num_shards: int) -> int:
    """Return a deterministic shard index (0..num_shards-1) for a key."""
    digest = hashlib.md5(key.encode('utf-8')).hexdigest()
    return int(digest, 16) % num_shards


…

14 0 Open

Database scaling & optimization easy

Rebalance Shard Ranges Across Nodes in Python

A mock rebalancing function that shuffles shard ranges and distributes them evenly across nodes using round-robin assignment.

sharding rebalancing dataclass

Python

import random
from dataclasses import dataclass

@dataclass
class Shard:
    id: int
    start: int
    end: int

def rebalance_shards(shards: list[Shard], node_count: int) -> dict[int, list[Shard]]:
    """Mock rebalancing of shard ranges across nodes."""
    all_ranges = [(s.start, s.end) for s in shards]
    random…

11 0 Open

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