afruzan

اولا که بهترین روش که ایده خودم هست استفاده از partitioning در دیتابیس هایی که ممکن باشه هست ولی اگر ممکن نبود (مانند sqlite) باید به کارایی دقت زیادی کرد. در این موارد اگر جدول مربوطه فایل های وابسته حجیمی داشته باشه یه راهکار اینه ابتدا از حذف منطقی برای حذف کردن فایل های و تصاویر وابسته استفاده کرد و در فواصل زمانی بیشتر زمانی که کار سیستم سبک تره حذف واقعی انجام داد.

به هر حال برای انجام فرآیند حذف موارد زیر مهم اند:

If your query affects 5000 rows or more in the same table, that table gets locked during the operation. This is standard SQL Server behavior. Basically every DELETE causes a lock on that row and every 5000 row locks on the same table cause a Lock Escalation from row to table.

declare @MoreRowsToDelete bit

afruzan

// convert flat array of items to pivot table data
// uses linq.js

import Enumerable from 'linq';

export interface Column {
  columnName: string;
  sourceField: string;
  sourceValue?: string;
  isTotal?: boolean;

afruzan

using System.Collections.Concurrent;
using System.Linq.Expressions;
using System.Reflection;

namespace Afruzan.Shared.EventBus;

public class LocalEventBus : IEventBus
{
    public LocalEventBus()
    {

afruzan

// JS array equivalents to C# LINQ methods - by Dan B.

// Here's a simple array of "person" objects
var people = [ 
	{ name: "John", age: 20 }, 
	{ name: "Mary", age: 35 }, 
	{ name: "Arthur", age: 78 }, 
	{ name: "Mike", age: 27 }, 
	{ name: "Judy", age: 42 }, 
	{ name: "Tim", age: 8 } 

afruzan

export class RetryPolicy<T> {

  constructor(
    private action: () => Promise<T>,
    private retryDelays: number[]) {

  }

  private retryNumber;

afruzan

import { HubConnection, HubConnectionBuilder, IHttpConnectionOptions, LogLevel, MessageHeaders } from '@microsoft/signalr';
import { Observable } from 'rxjs';
import { Subject } from 'rxjs';
import { map } from 'rxjs/operators';
import { AuthService } from '../auth.service';
import { RetryCanceledError, RetryPolicy } from './retry-policy';

export abstract class SignalRHubBase {

  constructor(private authService: AuthService) {

afruzan

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Options;

namespace SignalRWebApp

afruzan

// a query on db without any think on database data structure:
// (NullIfEmpty is my function on T[].)
var shardsBounds = context.Storages
                .Select(i => new ShardBounds
                {
                    StorageCode = i.StorageCode,
                    StartDateTime = i.StartDateTime,
                    EndDateTime = i.EndDateTime,
                    PlateReaderIds = i.StoragePlateReaders.Select(i => i.PlateReaderId).ToArray().NullIfEmpty(),
                });

afruzan

declare @myutcdate as datetime2 = CAST('2021-03-17 22:00' AS datetime2);

select 
FORMAT(SWITCHOFFSET(@myutcdate, '+03:30'), 'yyyy-MM-dd', 'fa') as 'get iran date',
FORMAT(SWITCHOFFSET(@myutcdate, '+03:30'), 'yyyy-MM', 'fa') as 'get iran year-month',
CAST(FORMAT(SWITCHOFFSET(@myutcdate, '+03:30'), 'dd', 'fa') as int) as 'get iran day',
CAST(FORMAT(@myutcdate, 'dd', 'fa') as int) as 'invalid time-zone results in invalid date.'

afruzan

    public class Program
    {
        private static DateTime _startupTimestamp;

        public static void Main(string[] args)
        {
            _startupTimestamp = DateTime.Now;
            CreateHostBuilder(args).Build().Run();
        }