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Database scaling & optimization

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

3 matches

Approximate Count with HyperLogLog in Python

A mock HyperLogLog implementation uses hash-based registers to estimate cardinality of large datasets with sublinear memory.

hyperloglog cardinality hash

Python

import hashlib

class HyperLogLog:
    def __init__(self, precision=4):
        if precision < 4 or precision > 16:
            raise ValueError("precision must be between 4 and 16")
        self.precision = precision
        self.registers = [0] * (1 << precision)

    def _hash(self, value):
        return int(hashl…

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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