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Database scaling & optimization

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

4 matches

Cross Shard Query Scatter Gather Mock in Python

Simulate a distributed database cross-shard query using a scatter-gather pattern with a mock Python implementation.

scatter-gather sharding distributed-systems

from dataclasses import dataclass
from typing import List, Dict


@dataclass
class NodeResponse:
    node_id: int
    data: Dict[str, float]


def mock_query_shard(shard_id: int, shard_data: Dict[str, float], query: str) -> NodeResponse:
    """Simulate querying a single shard, returning matches whose value > 50."""
 …

13 0 Open

Database scaling & optimization medium

How to Eager Load with JOIN to Reduce N+1 Queries in Python

Demonstrates eager loading with a SQL JOIN to reduce N+1 query patterns down to a single database call when fetching related data.

eager-loading n-plus-1 join

Python

import sqlite3


def eager_load_join_reduce(mock_db_path=":memory:"):
    """Demonstrate eager loading where joins reduce query count from N+1 to 1."""
    conn = sqlite3.connect(mock_db_path)
    cursor = conn.cursor()
    cursor.executescript(
        """
        CREATE TABLE authors (id INTEGER PRIMARY KEY, name TE…

16 0 Open

Database scaling & optimization medium

How to mock batch commit of transactions in Python

Simulate a transaction batch writer with commit, rollback, and summary logic to test database write patterns without a real database.

transactions mock batch

Python

import json
from datetime import datetime, timezone

class TransactionBatch:
    def __init__(self):
        self.pending = []
        self.committed = []
        self._log = []

    def add(self, operation):
        self.pending.append(operation)

    def commit(self):
        if not self.pending:
            return …

16 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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