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Database scaling & optimization

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

4 matches

How to Build a Shard Map Mock Dict in Python

Implement a dictionary-like class that distributes keys across multiple shards using Python's hash() for realistic data partitioning.

dict sharding hash

Python

class ShardMap:
    def __init__(self, shard_count):
        self.shards = {i: {} for i in range(shard_count)}
        self.shard_count = shard_count

    def _shard_for(self, key):
        return hash(key) % self.shard_count

    def __getitem__(self, key):
        return self.shards[self._shard_for(key)][key]

    d…

14 0 Open

Database scaling & optimization medium

How to Implement Consistent Hashing in Python

Build a consistent hash ring in Python that distributes keys across nodes and minimizes remapping when nodes are added or removed.

consistent-hashing distributed-systems sharding

Python

import hashlib
from bisect import bisect_right


class ConsistentHashRing:
    def __init__(self, nodes, replicas=3):
        self.replicas = replicas
        self.ring = {}
        self.sorted_keys = []
        for node in nodes:
            self.add_node(node)

    def _hash(self, key):
        return int(hashlib.md…

15 0 Open

Database scaling & optimization medium

How to Implement Keyset Pagination in Python (Seek Method)

Implement keyset (seek) pagination in Python with a mock paginator that efficiently fetches pages based on the last row rather than OFFSET.

pagination keyset seek-method

Python

from dataclasses import dataclass
from typing import List, Optional


@dataclass
class Row:
    id: int
    name: str

    def __lt__(self, other: "Row") -> bool:
        return (self.id, self.name) < (other.id, other.name)


class MockKeysetPaginator:
    """Pagination using keyset (seek) method instead of OFFSET."""…

14 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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