linq to sql join优化

初始 时间:常超时
---------------------------
var innerJoinQuery = from ca in context.caccey
join cls in context.cclass on ca.caccey_cclassid equals cls.cclass_cclassID
join stl in context.cstyle on ca.caccey_cstyleid equals stl.cstyle_cstyleID
join loc in context.Custom_Captions on ca.caccey_location equals loc.Capt_Code
join suloc in context.subloc on ca.caccey_sublocid equals suloc.subloc_sublocID
where string.Compare(ca.caccey_Name, barCode, true) == 0
&& string.Compare(loc.Capt_FamilyType, "Choices", true) == 0 && string.Compare(loc.Capt_Family, "lists_location", true) == 0
select new Garnishry
{
Id = ca.caccey_cacceyID,
Name = ca.caccey_Name,
ItemNo = ca.caccey_itemno,
MaterialId = ca.caccey_cqualyid,
Stone = ca.caccey_stone,
ClassId = ca.caccey_cclassid,
StyleId = ca.caccey_cstyleid,
LocationId = ca.caccey_location,
Location = new StocktakingLocation
{
AreaCode = loc.Capt_Code,
AreaName = loc.Capt_CS
},
SubLocationId = ca.caccey_sublocid,
SubLocation = new SubLocation
{
Id = suloc.subloc_sublocID,
SubLocationName = suloc.subloc_Name.Trim()
},
ItemName = ca.caccey_itemname
};

第一次优化 时间：第1次11~15s ,第2次 3~4s,第3次 1s
----------------------
var innerJoinQuery = from ca in context.caccey
join cls in context.cclass on ca.caccey_cclassid equals cls.cclass_cclassID
join stl in context.cstyle on ca.caccey_cstyleid equals stl.cstyle_cstyleID
join loc in context.Custom_Captions on ca.caccey_location equals loc.Capt_Code
join suloc in context.subloc on ca.caccey_sublocid equals suloc.subloc_sublocID into caGroup
from suLocItem in caGroup.DefaultIfEmpty()
where string.Compare(ca.caccey_Name, barCode, true) == 0
&& string.Compare(loc.Capt_FamilyType, "Choices", true) == 0 && string.Compare(loc.Capt_Family, "lists_location", true) == 0
select new Garnishry
{
Id = ca.caccey_cacceyID,
Name = ca.caccey_Name,
ItemNo = ca.caccey_itemno,
MaterialId = ca.caccey_cqualyid,
Stone = ca.caccey_stone,
ClassId = ca.caccey_cclassid,
Class = cls.cclass_Name,
StyleId = ca.caccey_cstyleid,
Style = stl.cstyle_Name,
LocationId = ca.caccey_location,
Location = new StocktakingLocation
{
AreaCode = loc.Capt_Code,
AreaName = loc.Capt_CS
},
SubLocationId = ca.caccey_sublocid,
SubLocation = ca.caccey_sublocid.HasValue ? new SubLocation
{
Id = suLocItem.subloc_sublocID,
SubLocationName = suLocItem.subloc_Name.Trim()
} : null,
ItemName = ca.caccey_itemname
};

第二次优化 时间：第1次5~8s ,第2次 1~2s,第3次 1s
---------------------------------

var innerJoinQuery = from ca in context.caccey.Where(ca2 => string.Compare(ca2.caccey_Name, barCode, true) == 0)
join cls in context.cclass on ca.caccey_cclassid equals cls.cclass_cclassID into caCls
from caCls1 in caCls.DefaultIfEmpty()
join stl in context.cstyle on ca.caccey_cstyleid equals stl.cstyle_cstyleID
join loc in context.Custom_Captions.Where(loc2 => string.Compare(loc2.Capt_FamilyType, "Choices", true) == 0 && string.Compare(loc2.Capt_Family, "lists_location", true) == 0)
on ca.caccey_location equals loc.Capt_Code
join suloc in context.subloc on ca.caccey_sublocid equals suloc.subloc_sublocID into caGroup
from suLocItem in caGroup.DefaultIfEmpty()
//where string.Compare(ca.caccey_Name, barCode, true) == 0&&
//string.Compare(loc.Capt_FamilyType, "Choices", true) == 0 && string.Compare(loc.Capt_Family, "lists_location", true) == 0
select new Garnishry
{
Id = ca.caccey_cacceyID,
Name = ca.caccey_Name,
ItemNo = ca.caccey_itemno,
MaterialId = ca.caccey_cqualyid,
Stone = ca.caccey_stone,
ClassId = ca.caccey_cclassid,
Class = caCls1.cclass_Name,
StyleId = ca.caccey_cstyleid,
Style = stl.cstyle_Name,
LocationId = ca.caccey_location,
Location = new StocktakingLocation
{
AreaCode = loc.Capt_Code,
AreaName = loc.Capt_CS
},
SubLocationId = ca.caccey_sublocid,
SubLocation = ca.caccey_sublocid.HasValue ? new SubLocation
{
Id = suLocItem.subloc_sublocID,
SubLocationName = suLocItem.subloc_Name.Trim()
} : null,
ItemName = ca.caccey_itemname
};

第三次优化 时间：第1次3~5s ,第2次 1s
-------------------------------

Garnishry g = (from t in context.caccey
where string.Compare(t.caccey_Name, barCode, true) == 0
select new Garnishry()
{
Id = t.caccey_cacceyID,
Name = t.caccey_Name,
ItemNo = t.caccey_itemno,
MaterialId = t.caccey_cqualyid,
Stone = t.caccey_stone,
ClassId = t.caccey_cclassid,
StyleId = t.caccey_cstyleid,
LocationId = t.caccey_location,
SubLocationId = t.caccey_sublocid,
ItemName = t.caccey_itemname
}).FirstOrDefault();

if (g != null)
{
var innerJoinQuery = from cls in context.cclass.Where(cls2 => cls2.cclass_cclassID == g.ClassId)
join stl in context.cstyle on g.StyleId equals stl.cstyle_cstyleID
join loc in context.Custom_Captions.Where(loc2 => string.Compare(loc2.Capt_FamilyType, "Choices", true) == 0 && string.Compare(loc2.Capt_Family, "lists_location", true) == 0)
on g.LocationId equals loc.Capt_Code
join suloc in context.subloc on g.SubLocationId equals suloc.subloc_sublocID into caGroup
from suLocItem in caGroup.DefaultIfEmpty()
select new Garnishry
{
Id = g.Id,
Name = g.Name,
ItemNo = g.ItemNo,
MaterialId = g.MaterialId,
Stone = g.Stone,

ClassId = g.ClassId,
Class = cls.cclass_Name,

StyleId = g.StyleId,
Style = stl.cstyle_Name,

LocationId = g.LocationId,
Location = new StocktakingLocation
{
AreaCode = loc.Capt_Code,
AreaName = loc.Capt_CS
},

SubLocationId = g.SubLocationId,
SubLocation = g.SubLocationId.HasValue ? new SubLocation
{
Id = suLocItem.subloc_sublocID,
SubLocationName = suLocItem.subloc_Name.Trim()
} : null,
ItemName = g.ItemName
};
g = innerJoinQuery.FirstOrDefault();
}
第四次优化 时间：第1次 1s
---------------
在数据库中对相关字段创建索引。尤其是数据量大的数据表。

结论：
-----------------
前几次优化，不如直接到数据库建索引优化。