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Database scaling & optimization

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

3 matches

How to Create a Covering Index with INCLUDE Columns in Python

Create a covering index with INCLUDE columns in SQLite from Python and inspect the query plan to confirm the index covers the query.

sqlite indexing covering index

Python

import sqlite3

def create_covering_index_mock():
    conn = sqlite3.connect(":memory:")
    cursor = conn.cursor()

    cursor.execute("""
        CREATE TABLE employees (
            id INTEGER PRIMARY KEY,
            name TEXT,
            department TEXT,
            salary INTEGER
        )
    """)

    employe…

15 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 medium

Mock CQRS Read/Write Split in Python

Separate order mutations from queries using a read model and write model to mock CQRS-style separation of concerns.

cqrs read-write dataclass

Python

from dataclasses import dataclass, field
from typing import List, Dict


@dataclass
class Order:
    id: int
    amount: float
    status: str = "pending"


class OrderWriteModel:
    """Handles all mutations (writes) to orders."""

    def __init__(self):
        self._orders: Dict[int, Order] = {}
        self._next…

12 0 Open

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