加快linq权利查询

Question

我目前有一个查询,由于数据库中的数据量不会花费很长时间,有时会崩溃.

有人可以注意到我能做些什么来帮助加快速度吗？

public IList<Report> GetReport(CmsEntities context, long manufacturerId, long? regionId, long? vehicleTypeId)
        {
            var now = DateTime.Now;
            var today = new DateTime(now.Year, now.Month, 1);
            var date1monthago = today.AddMonths(-1);
            var date2monthago = today.AddMonths(-2);
            var date3monthago = today.AddMonths(-3);
            var date4monthago = today.AddMonths(-4);
            var date5monthago = today.AddMonths(-5);
            var date6monthago = today.AddMonths(-6);
            today = TimeManager.EndOfDay(new DateTime(now.AddMonths(-1).Year, today.AddMonths(-1).Month, DateTime.DaysInMonth(now.Year, today.AddMonths(-1).Month)));             
            var query = from item in context.Invoices
                         where item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Select(x => x.ManufacturerId).Contains(manufacturerId)
                         && (item.InvoiceDate >= date6monthago && item.InvoiceDate <= today)
                         && (regionId.HasValue && regionId.Value > 0 ? item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Select(x => x.RegionId).Contains(regionId.Value) : true)
                         && (item.InvType == "I" || item.InvType == null)
                         && (vehicleTypeId.HasValue && vehicleTypeId.Value > 0 ? item.Repair.Job.Vehicle.Model.VehicleTypes.Select(x => x.Id).Contains(vehicleTypeId.Value) : true)
                         select item;

            var query2 = from item in query
                         group item by new { item.Repair.Job.Bodyshop } into g
                         let manufJobs = query.Where(x => x.Repair.Job.Vehicle.Model.ManufacturerId == manufacturerId && x.Repair.Job.BodyshopId == g.Key.Bodyshop.Id)
                         let allJobs = query.Where(x => x.Repair.Job.BodyshopId == g.Key.Bodyshop.Id)
                         select new tReport
                         {                                     
    MonthSixManufJobTotal = manufJobs.Where(x => x.InvoiceDate.Month == date6monthago.Month && x.InvoiceDate.Year == date6monthago.Year).GroupBy(x => x.Repair.Job).Count(),
    MonthSixJobTotal = allJobs.Where(x => x.InvoiceDate.Month == date6monthago.Month && x.InvoiceDate.Year == date6monthago.Year).GroupBy(x => x.Repair.Job).Count(),

    MonthFiveManufJobTotal = manufJobs.Where(x => x.InvoiceDate.Month == date5monthago.Month && x.InvoiceDate.Year == date5monthago.Year).GroupBy(x => x.Repair.Job).Count(),
    MonthFiveJobTotal = allJobs.Where(x => x.InvoiceDate.Month == date5monthago.Month && x.InvoiceDate.Year == date5monthago.Year).GroupBy(x => x.Repair.Job).Count(),

    MonthFourManufJobTotal = manufJobs.Where(x => x.InvoiceDate.Month == date4monthago.Month && x.InvoiceDate.Year == date4monthago.Year).GroupBy(x => x.Repair.Job).Count(),
    MonthFourJobTotal = allJobs.Where(x => x.InvoiceDate.Month == date4monthago.Month && x.InvoiceDate.Year == date4monthago.Year).GroupBy(x => x.Repair.Job).Count(),

    MonthThreeManufJobTotal = manufJobs.Where(x => x.InvoiceDate.Month == date3monthago.Month && x.InvoiceDate.Year == date3monthago.Year).GroupBy(x => x.Repair.Job).Count(),
    MonthThreeJobTotal = allJobs.Where(x => x.InvoiceDate.Month == date3monthago.Month && x.InvoiceDate.Year == date3monthago.Year).GroupBy(x => x.Repair.Job).Count(),

    MonthTwoManufJobTotal = manufJobs.Where(x => x.InvoiceDate.Month == date2monthago.Month && x.InvoiceDate.Year == date2monthago.Year).GroupBy(x => x.Repair.Job).Count(),
    MonthTwoJobTotal = allJobs.Where(x => x.InvoiceDate.Month == date2monthago.Month && x.InvoiceDate.Year == date2monthago.Year).GroupBy(x => x.Repair.Job).Count(),

    MonthOneManufJobTotal = manufJobs.Where(x => x.InvoiceDate.Month == date1monthago.Month && x.InvoiceDate.Year == date1monthago.Year).GroupBy(x => x.Repair.Job).Count(),
    MonthOneJobTotal = allJobs.Where(x => x.InvoiceDate.Month == date1monthago.Month && x.InvoiceDate.Year == date1monthago.Year).GroupBy(x => x.Repair.Job).Count(),

    ManufTotal = manufJobs.GroupBy(x => x.Repair.Job).Count(),
    Total = allJobs.GroupBy(x => x.Repair.Job).Count(),

    PercentageOf = ((decimal)manufJobs.GroupBy(x => x.Repair.Job).Count() / (decimal)allJobs.GroupBy(x => x.Repair.Job).Count()) * 100
                         };

            return query2.OrderBy(x => x).ToList();
        }

编辑

var query = from item in context.Invoices.AsNoTracking()
                    where item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(x => x.ManufacturerId == manufacturerId)
                    && (item.InvoiceDate >= date12monthago && item.InvoiceDate <= today)
                    && (item.InvType == "I" || item.InvType == null)
                    select item;

        if (regionId.HasValue && regionId.Value > 0)
        {
            query = query.Where(item => item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Select(x => x.RegionId).Contains(regionId.Value));
        }

        if (vehicleTypeId.HasValue && vehicleTypeId.Value > 0)
        {
            query = query.Where(item => item.Repair.Job.Vehicle.Model.VehicleTypes.Select(x => x.Id).Contains(vehicleTypeId.Value));
        }


              var query2 = from item in hey
                     group item by new { item.Repair.Job.Bodyshop, item.InvoiceDate.Month } into m
                     select new TReport
                     {
                         Bodyshop = m.Key.Bodyshop.Name,
                         Bays = m.Key.Bodyshop.Bays,
                         Region = m.Key.Bodyshop.Manufacturer2Bodyshop.FirstOrDefault(x => x.ManufacturerId == manufacturerId).Region.Name,
                         BodyshopCode = m.Key.Bodyshop.Manufacturer2Bodyshop.FirstOrDefault(x => x.ManufacturerId == manufacturerId).BodyshopCode,
                         Total = m.Count(),
                         ManufTotal = m.Where(x => x.Repair.Job.Vehicle.Model.ManufacturerId == manufacturerId).Count(),
                         Totals = m.GroupBy(j => j.InvoiceDate.Month).Select(j => new TPercentReportInner
                         {
                             Month = j.Key,
                             ManufTotal = j.Where(x => x.Repair.Job.Vehicle.Model.ManufacturerId == manufacturerId).Count(),
                             AllTotal = j.Count()
                         })
                     };

我切断了查询.但即使现在表现比以前更差？

Answer 1

我首先从查询中删除硬编码的可选条件,这将允许查询优化器根据您拥有的参数使用不同的查询计划,例如:

var query = from item in context.Invoices.AsNoTracking()
            where item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Select(x => x.ManufacturerId).Contains(manufacturerId)
            && (item.InvoiceDate >= date12monthago && item.InvoiceDate <= today)
            && (item.InvType == "I" || item.InvType == null)
            select item;

if (regionId.HasValue && regionId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Select(x => x.RegionId).Contains(regionId.Value));

if (vehicleTypeId.HasValue && vehicleTypeId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Vehicle.Model.VehicleTypes.Select(x => x.Id).Contains(vehicleTypeId.Value));

var query2 = from item in query
             group item by new { item.InvoiceDate.Month, item.Repair.Job.Bodyshop } into g
             select new TReport
             {
                 BodyshopId = g.Key.Bodyshop.Id,  
                 Month = g.Key.Month,
                 MonthAllJobTotal = g.Count()
             };

return query2.ToList();

您还可以检查是否转换.Select(x=>x.id).Contains(id)或.Any(x=>x.Id==id)执行速度更快,尽管我认为它们在查询计划和执行速度方面会相似.那会给你:

var query = from item in context.Invoices.AsNoTracking()
            where item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.ManufacturerId==manufacturerId)
            && (item.InvoiceDate >= date12monthago && item.InvoiceDate <= today)
            && (item.InvType == "I" || item.InvType == null)
            select item;

if (regionId.HasValue && regionId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.RegionId==regionId.Value));

if (vehicleTypeId.HasValue && vehicleTypeId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Vehicle.Model.VehicleTypes.Any(v=>v.Id==vehicleTypeId.Value));

var query2 = from item in query
             group item by new { item.InvoiceDate.Month, item.Repair.Job.Bodyshop } into g
             select new TReport
             {
                 BodyshopId = g.Key.Bodyshop.Id,  
                 Month = g.Key.Month,
                 MonthAllJobTotal = g.Count()
             };

return query2.ToList();

根据你所拥有的,我猜你会.AsNoTracking()为你做的很少,但它不会受到伤害.它在检索大量实体时会产生更大的影响,而这似乎并没有发生.

然后,我会通过删除硬编码的ManufacturerId来清理和标准化您的查询,这将为您提供:

var query = from item in context.Invoices.AsNoTracking()
            where (item.InvoiceDate >= date12monthago && item.InvoiceDate <= today)
            && (item.InvType == "I" || item.InvType == null)
            select item;

if (manufacturerId.HasValue && manufacturerId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.ManufacturerId==manufacturerId));

if (regionId.HasValue && regionId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.RegionId==regionId.Value));

if (vehicleTypeId.HasValue && vehicleTypeId.Value > 0)
    query=query.Where(item=>item.Repair.Job.Vehicle.Model.VehicleTypes.Any(v=>v.Id==vehicleTypeId.Value));

var query2 = from item in query
             group item by new { item.InvoiceDate.Month, item.Repair.Job.Bodyshop } into g
             select new TReport
             {
                 BodyshopId = g.Key.Bodyshop.Id,  
                 Month = g.Key.Month,
                 MonthAllJobTotal = g.Count()
             };

return query2.ToList();

然后,我会返回一个IQueryable而不是List,这样如果你不需要一个或多个列,它们可以从最终查询中删除,如:

public IQueryable<Report> GetReport(CmsEntities context, long? manufacturerId, long? regionId, long? vehicleTypeId)
    {
{
        var now = DateTime.Now;
        var today = new DateTime(now.Year, now.Month, 1);
        var date1monthago = today.AddMonths(-1);
        var date2monthago = today.AddMonths(-2);
        var date3monthago = today.AddMonths(-3);
        var date4monthago = today.AddMonths(-4);
        var date5monthago = today.AddMonths(-5);
        var date6monthago = today.AddMonths(-6);
        today = TimeManager.EndOfDay(new DateTime(now.AddMonths(-1).Year, today.AddMonths(-1).Month, DateTime.DaysInMonth(now.Year, today.AddMonths(-1).Month)));             

    var query = from item in context.Invoices.AsNoTracking()
                where (item.InvoiceDate >= date12monthago && item.InvoiceDate <= today)
                && (item.InvType == "I" || item.InvType == null)
                select item;

    if (manufacturerId.HasValue && manufacturerId.Value > 0)
        query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.ManufacturerId==manufacturerId));

    if (regionId.HasValue && regionId.Value > 0)
        query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.RegionId==regionId.Value));

    if (vehicleTypeId.HasValue && vehicleTypeId.Value > 0)
        query=query.Where(item=>item.Repair.Job.Vehicle.Model.VehicleTypes.Any(v=>v.Id==vehicleTypeId.Value));

    var query2 = from item in query
                 group item by new { item.InvoiceDate.Month, item.Repair.Job.Bodyshop } into g
                 select new TReport
                 {
                     BodyshopId = g.Key.Bodyshop.Id,  
                     Month = g.Key.Month,
                     MonthAllJobTotal = g.Count()
                 };

    return query2;
}

然后我将这些分开并将这些转换为扩展方法:

public static class MyExtensions 
{
    public static IQueryable<Invoice> Recent(this IQueryable<Invoice> context,long? manufacturerId=null,long? regionId=null,long? vehicleId=null)
    {
        var now = DateTime.Now;
        var today = new DateTime(now.Year, now.Month, 1);
        var date1monthago = today.AddMonths(-1);
        var date2monthago = today.AddMonths(-2);
        var date3monthago = today.AddMonths(-3);
        var date4monthago = today.AddMonths(-4);
        var date5monthago = today.AddMonths(-5);
        var date6monthago = today.AddMonths(-6);
        today = TimeManager.EndOfDay(new DateTime(now.AddMonths(-1).Year, today.AddMonths(-1).Month, DateTime.DaysInMonth(now.Year, today.AddMonths(-1).Month)));             

        var query = from item in context.Invoices.AsNoTracking()
                where (item.InvoiceDate >= date12monthago && item.InvoiceDate <= today)
                && (item.InvType == "I" || item.InvType == null)
                select item;

        if (manufacturerId.HasValue && manufacturerId.Value > 0)
            query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.ManufacturerId==manufacturerId));

        if (regionId.HasValue && regionId.Value > 0)
            query=query.Where(item=>item.Repair.Job.Bodyshop.Manufacturer2Bodyshop.Any(m=>m.RegionId==regionId.Value));

        if (vehicleTypeId.HasValue && vehicleTypeId.Value > 0)
            query=query.Where(item=>item.Repair.Job.Vehicle.Model.VehicleTypes.Any(v=>v.Id==vehicleTypeId.Value));
    return query;
}
public static IQueryable<Report> ToReport(this IQueryable<Invoice> context)
{
    return (from item in query
                 group item by new { item.InvoiceDate.Month, item.Repair.Job.Bodyshop } into g
                 select new TReport
                 {
                     BodyshopId = g.Key.Bodyshop.Id,  
                     Month = g.Key.Month,
                     MonthAllJobTotal = g.Count()
                 });

}
}

现在您可以执行以下操作:

var reports=db.Invoices.Recent.ToReport(); 

要么

var reports=db.Invoices.Recent(ManufacturerEnum.Toyota).ToReport();