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Database scaling & optimization

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

5 matches

Hash index equality mock concept in Python

A simple hash index class in Python that stores key-value pairs in buckets and demonstrates basic equality-based lookup.

hash-index hash-table database

Python

class HashIndex:
    def __init__(self):
        self._buckets = {}

    def insert(self, key, value):
        """Insert a key-value pair into the hash index."""
        index = hash(key) % 10
        if index not in self._buckets:
            self._buckets[index] = []
        self._buckets[index].append((key, value))…

12 0 Open

Database scaling & optimization easy

How to Replicate Data Across All Shards in Python

Mocks a global table that replicates a key-value pair to every shard, ensuring reads return the same value from any shard.

sharding replication distributed systems

Python

from dataclasses import dataclass
from typing import Dict, List


@dataclass
class Shard:
    id: str
    data: Dict[str, int]


class GlobalTable:
    def __init__(self, shards: List[Shard]):
        self._shards = {s.id: s for s in shards}

    def set_value(self, key: str, value: int) -> None:
        """Replicate …

14 0 Open

Database scaling & optimization easy

How to Speed Up Column Lookups with DataFrame Index in Python

Use pandas set_index to make repeated column value lookups O(1)-style fast instead of scanning the whole DataFrame each time.

pandas indexing performance

Python

import pandas as pd

# Mock dataset with duplicate customer IDs
data = {"customer_id": [101, 102, 103, 101, 104, 102],
        "order_amount": [250.0, 85.5, 300.0, 175.25, 420.0, 95.75]}

df = pd.DataFrame(data)
df = df.set_index("customer_id")

# Simulated lookup request
search_id = 102

# Fast index-based lookup (no…

15 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

Simulate a GIN Index for JSONB in Python

Build a mock Generalized Inverted Index (GIN) that flattens JSON documents into key-value tokens for fast lookup queries, mimicking PostgreSQL JSONB indexing.

jsonb gin-index inverted-index

Python

import json
import random
from collections import defaultdict

# Mock GIN (Generalized Inverted Index) for JSONB key-value pairs
class GINIndex:
    def __init__(self):
        self.posting_lists = defaultdict(list)  # token -> list of doc_ids
    
    def index(self, doc_id, json_obj):
        """Index a JSON documen…

14 0 Open

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