我有两个模型，Box和BoxLocations。 Box与hasMany有BoxLocations关系，而BoxLocations与belongsTo有Box关系。
BoxLocations还具有附加到模型的属性，该属性需要Box关系中的单个信息。
我注意到，在调用Box::with(['BoxLocations']->)all();时，我看到BoxLocations模型正在重新加载Box关系。每个BoxLocation（50次奇数次）都会发生这种情况
laravel是否不跟踪最初的Box::with(['BoxLocations']->)all();请求是否已加载Box，然后将其传递给BelongsTo关系？
我正在尝试优化Web系统，并在加载了take属性时（每次加载时同样需要它），对于已经加载的相同Box模型，它对数据库造成了50次奇怪的点击。
如果laravel不这样做-有更好的方法来实现上述目标吗？
答案 0 :(得分：0)
当您使用GO
/****** Object: Trigger [dbo].[Perfect_OJ] Script Date: 13/03/2019 13:11:06 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER TRIGGER [dbo].[Perfect_OJ]
ON [dbo].[CharQuests]
AFTER INSERT
AS
BEGIN
SET NOCOUNT ON;
DECLARE @QuestID INT = (SELECT QuestID FROM inserted)
IF @QuestID = 2222 -- The Perfect Orange Stats QuestID
BEGIN
DECLARE @CharID INT = (SELECT CharID FROM inserted)
DECLARE @UserUID INT = (SELECT UserUID FROM Chars WHERE CharID = @CharID)
DECLARE @ItemType TINYINT,
@RecRuneItemID INT
DECLARE @StatRecRuneItemID TABLE (StatRecRuneItemID INT) -- Str, Dex, Rec, Int, Wis, Luc
DECLARE @VitalRecRuneItemID TABLE (VitalRecRuneItemID INT) -- HP, MP, SP
DECLARE @GearTypes TABLE (GearTypes TINYINT) -- Gears, Capes and Shields
DECLARE @WeaponTypes TABLE (WeaponTypes TINYINT) -- Weapons and Accessories
-- The above tables were created in order to ensure a fast access to the types
-- of items that are to be recreated and the rune used to recreate them.
SET @ItemType = (SELECT Type FROM UserStoredItems WHERE UserUID = @UserUID AND Slot = 0)
SET @RecRuneItemID = (SELECT ItemID FROM UserStoredItems WHERE UserUID = @UserUID AND Slot = 1)
INSERT INTO @StatRecRuneItemID VALUES (100230),(100231),(100232),(100233),(100234),(100235)
-- ItemIDs of stat recreation runes (Str, Dex, Rec, Int, Wis, Luc, HP, MP, SP)
INSERT INTO @VitalRecRuneItemID VALUES (100236),(100237),(100238)
-- ItemIDs of vital stat recreation runes (HP, MP, SP)
INSERT INTO @GearTypes VALUES (16),(17),(18),(19),(20),(21),(24),(31),(32),(33),(34),(35),(36),(39),(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12),(13),(14),(15),(22),(23),(40),(72),(73),(74),(76),(77),(87),(88),(89),(91),(92),(96),(97)
-- Types of gears, capes. Here you can include anything you want to be rerollable with both stat and vital stat recreation runes.
INSERT INTO @WeaponTypes VALUES (16),(17),(18),(19),(20),(21),(24),(31),(32),(33),(34),(35),(36),(39),(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12),(13),(14),(15),(22),(23),(40),(72),(73),(74),(76),(77),(87),(88),(89),(91),(92),(96),(97)
-- Types of weapons, accessories. Here you can include anything you want to be rerollable only with stat recreation runes.
IF ((@ItemType IN (SELECT GearTypes FROM @GearTypes)) AND (@RecRuneItemID IN (SELECT StatRecRuneItemID FROM @StatRecRuneItemID) OR @RecRuneItemID IN (SELECT VitalRecRuneItemID FROM @VitalRecRuneItemID))) OR (@ItemType IN (SELECT WeaponTypes FROM @WeaponTypes) AND (@RecRuneItemID IN (SELECT StatRecRuneItemID FROM @StatRecRuneItemID)))
-- The above IF statement checks if the item to be recreated and the recreation rune are compatible with each other.
-- As you can see, it works only if it's an item with the Type from @GearTypes(gears, capes) and all recreation runes,
-- or if it's an item with the Type from @WeaponTypes(weapons, accessories) and stat recreation runes only.
BEGIN
DECLARE @Craftname VARCHAR(20),
@Str TINYINT,
@Dex TINYINT,
@Rec TINYINT,
@Int TINYINT,
@Wis TINYINT,
@Luc TINYINT,
@HP TINYINT,
@MP TINYINT,
@SP TINYINT,
@Enchant TINYINT,
@ItemID INT,
@ReqWis TINYINT,
@Server TINYINT,
@OJs TINYINT,
@NewOJs TINYINT,
@MaxedOJs TINYINT,
@LowestOJType VARCHAR(3),
@LowestOJ TINYINT
SET @Craftname = (SELECT Craftname FROM UserStoredItems WHERE UserUID = @UserUID AND Slot = 0)
SET @Str = CAST(SUBSTRING(@Craftname,1,2) AS TINYINT)
SET @Dex = CAST(SUBSTRING(@Craftname,3,2) AS TINYINT)
SET @Rec = CAST(SUBSTRING(@Craftname,5,2) AS TINYINT)
SET @Int = CAST(SUBSTRING(@Craftname,7,2) AS TINYINT)
SET @Wis = CAST(SUBSTRING(@Craftname,9,2) AS TINYINT)
SET @Luc = CAST(SUBSTRING(@Craftname,11,2) AS TINYINT)
SET @HP = CAST(SUBSTRING(@Craftname,13,2) AS TINYINT)
SET @MP = CAST(SUBSTRING(@Craftname,15,2) AS TINYINT)
SET @SP = CAST(SUBSTRING(@Craftname,17,2) AS TINYINT)
SET @Enchant = CAST(SUBSTRING(@Craftname,19,2) AS TINYINT)
SET @ItemID = (SELECT ItemID FROM UserStoredItems WHERE UserUID = @UserUID AND Slot = 0)
SET @ReqWis = (SELECT ReqWis FROM PS_GameDefs.dbo.Items WHERE ItemID = @ItemID)
-- Get the maximum possible OJ on the item
SET @Server = (SELECT Server FROM PS_GameDefs.dbo.Items WHERE ItemID = @ItemID)
-- Get the maximum amount of OJs on the item
DECLARE @AllOJs TABLE (StatName VARCHAR(3), Stats TINYINT)
INSERT INTO @AllOJs VALUES ('Str',@Str),('Dex',@Dex),('Rec',@Rec),('Int',@Int),('Wis',@Wis),('Luc',@Luc),('HP',@HP),('MP',@MP),('SP',@SP)
-- Declaring the @AllOJs table and storing the OJs of the item before the recreation process.
SET @OJs = (SELECT COUNT(*) FROM @AllOJs WHERE Stats > 0) -- Getting the amount of OJs
SET @MaxedOJs = (SELECT COUNT(*) FROM @AllOJs WHERE Stats = @ReqWis) -- Getting the amount of MaxedOJs
IF (@OJs <= @Server) AND (@MaxedOJs < @Server)
-- Checking if there's still room for another perfect OJ.
BEGIN
DECLARE @NewStr TINYINT,
@NewDex TINYINT,
@NewRec TINYINT,
@NewInt TINYINT,
@NewWis TINYINT,
@NewLuc TINYINT,
@NewHP TINYINT,
@NewMP TINYINT,
@NewSP TINYINT,
@NewEnchant TINYINT
-- Declaring the new variables, where the new orange stats will be stored
SET @NewStr = @Str
SET @NewDex = @Dex
SET @NewRec = @Rec
SET @NewInt = @Int
SET @NewWis = @Wis
SET @NewLuc = @Luc
SET @NewHP = @HP
SET @NewMP = @MP
SET @NewSP = @SP
SET @NewEnchant = @Enchant
-- Assigning the old OJs to the new OJ variables
IF @RecRuneItemID = 100230 -- STR Rec Rune
BEGIN
SET @NewStr = @ReqWis
END
ELSE IF @RecRuneItemID = 100231 -- DEX Rec Rune
BEGIN
SET @NewDex = @ReqWis
END
ELSE IF @RecRuneItemID = 100232 -- REC Rec Rune
BEGIN
SET @NewRec = @ReqWis
END
ELSE IF @RecRuneItemID = 100233 -- INT Rec Rune
BEGIN
SET @NewInt = @ReqWis
END
ELSE IF @RecRuneItemID = 100234 -- WIS Rec Rune
BEGIN
SET @NewWis = @ReqWis
END
ELSE IF @RecRuneItemID = 100235 -- LUC Rec Rune
BEGIN
SET @NewLuc = @ReqWis
END
ELSE IF @RecRuneItemID = 100236 -- HP Rec Rune
BEGIN
SET @NewHP = @ReqWis
END
ELSE IF @RecRuneItemID = 100237 -- MP Rec Rune
BEGIN
SET @NewMP = @ReqWis
END
ELSE IF @RecRuneItemID = 100238 -- SP Rec Rune
BEGIN
SET @NewSP = @ReqWis
END
END
ELSE GOTO FAIL
END -- End of the case where both items are good and compatible with each other
ELSE GOTO FAIL
-- In the case where the item and the rec rune aren't compatible with each other,
-- the process will end. No modifications to the item will occur.
CHECKOJAMOUNT:
-- This label checks if after the reroll there aren't more
-- types of orange stats than the item can normally have.
DECLARE @NewAllOJs TABLE (StatName VARCHAR(3), Stats TINYINT)
INSERT INTO @NewAllOJs VALUES ('Str',@NewStr),('Dex',@NewDex),('Rec',@NewRec),('Int',@NewInt),('Wis',@NewWis),('Luc',@NewLuc),('HP',@NewHP),('MP',@NewMP),('SP',@NewSP)
-- Declaring the @NewAllOJs table and assigning the new OJs to it.
SET @NewOJs = (SELECT COUNT(*) FROM @NewAllOJs WHERE Stats > 0)
-- Getting the amount of OJs on the item after the reroll.
IF @NewOJs > @Server
-- If the amount is bigger than what the item can normally have,
-- the lowest stat, that is bigger than zero of course, is going to be removed.
-- e.g. If the item allows max 4 orange stats, max stat being 40,
-- it has 40 STR, 40 DEX, 40 REC, 39 LUC, and we want to use a HP Rec Rune on it.
-- After the reroll process it will have 4000 HP, 40 STR, 40 DEX, 40 REC and 0 LUC.
BEGIN
SET @LowestOJType = (SELECT StatName FROM @NewAllOJs WHERE Stats = (SELECT MIN(Stats) FROM @NewAllOJs WHERE Stats > 0))
-- Getting the lowest stat.
IF @LowestOJType = 'Str'
SET @NewStr = 0
ELSE IF @LowestOJType = 'Dex'
SET @NewDex = 0
ELSE IF @LowestOJType = 'Rec'
SET @NewRec = 0
ELSE IF @LowestOJType = 'Int'
SET @NewInt = 0
ELSE IF @LowestOJType = 'Wis'
SET @NewWis = 0
ELSE IF @LowestOJType = 'Luc'
SET @NewLuc = 0
ELSE IF @LowestOJType = 'HP'
SET @NewHP = 0
ELSE IF @LowestOJType = 'MP'
SET @NewMP = 0
ELSE IF @LowestOJType = 'SP'
SET @NewSP = 0
-- Whichever the lowest stat is, it is changed to 0.
END
CRAFTNAMEUPDATE:
-- This label is responsible for applying the new orange stat to the item.
DECLARE @FinalStr VARCHAR(2),
@FinalDex VARCHAR(2),
@FinalRec VARCHAR(2),
@FinalInt VARCHAR(2),
@FinalWis VARCHAR(2),
@FinalLuc VARCHAR(2),
@FinalHP VARCHAR(2),
@FinalMP VARCHAR(2),
@FinalSP VARCHAR(2),
@FinalEnchant VARCHAR(2)
-- As Craftname is a varchar(20), we need to create it out of varchars.
SET @FinalStr = CAST(@NewStr AS VARCHAR(2))
SET @FinalDex = CAST(@NewDex AS VARCHAR(2))
SET @FinalRec = CAST(@NewRec AS VARCHAR(2))
SET @FinalInt = CAST(@NewInt AS VARCHAR(2))
SET @FinalWis = CAST(@NewWis AS VARCHAR(2))
SET @FinalLuc = CAST(@NewLuc AS VARCHAR(2))
SET @FinalHP = CAST(@NewHP AS VARCHAR(2))
SET @FinalMP = CAST(@NewMP AS VARCHAR(2))
SET @FinalSP = CAST(@NewSP AS VARCHAR(2))
SET @FinalEnchant = CAST(@NewEnchant AS VARCHAR(2))
-- Assigning the new OJs to the respective varchar(2) variables.
IF LEN(@FinalStr) < 2
BEGIN
SET @FinalStr = '0' + @FinalStr
END
IF LEN(@FinalDex) < 2
BEGIN
SET @FinalDex = '0' + @FinalDex
END
IF LEN(@FinalRec) < 2
BEGIN
SET @FinalRec = '0' + @FinalRec
END
IF LEN(@FinalInt) < 2
BEGIN
SET @FinalInt = '0' + @FinalInt
END
IF LEN(@FinalWis) < 2
BEGIN
SET @FinalWis = '0' + @FinalWis
END
IF LEN(@FinalLuc) < 2
BEGIN
SET @FinalLuc = '0' + @FinalLuc
END
IF LEN(@FinalHP) < 2
BEGIN
SET @FinalHP = '0' + @FinalHP
END
IF LEN(@FinalMP) < 2
BEGIN
SET @FinalMP = '0' + @FinalMP
END
IF LEN(@FinalSP) < 2
BEGIN
SET @FinalSP = '0' + @FinalSP
END
IF LEN(@FinalEnchant) < 2
BEGIN
SET @FinalEnchant = '0' + @FinalEnchant
END
-- The above 10 blocks are here to ensure that each orange stat varchar(2) is actually 2 digit long.
UPDATE UserStoredItems
SET Craftname = @FinalStr + @FinalDex + @FinalRec + @FinalInt + @FinalWis + @FinalLuc + @FinalHP + @FinalMP + @FinalSP + @FinalEnchant
WHERE UserUID = @UserUID AND Slot = 0
-- The above block updates the Craftname of the item.
DELETERUNE:
-- This label removes the recreation rune.
-- As you can see, it removes just one recreation rune, not the whole stack.
UPDATE UserStoredItems
SET Count = Count-1
WHERE UserUID = @UserUID AND Slot = 1
-- Decrementing the amount of recreation runes
DELETE FROM UserStoredItems
WHERE UserUID = @UserUID AND Slot = 1 AND Count = 0
-- If after decrementing the amount of recreation runes the amount is 0, delete the row from the database.
END
FAIL:
-- This label is called from above a couple of times,
-- in case the recreation requirements aren't met.
DELETEQUEST:
-- This label deletes the recreation quest.
DELETE FROM CharQuests
WHERE CharID = @CharID AND QuestID = @QuestID
END
`
方法时，Laravel使用eager loading。
当访问口才关系作为属性时，关系数据是“延迟加载”的。这意味着直到您首次访问该属性，关系数据才被实际加载。但是，Eloquent可以在查询父模型时“急于加载”关系。积极的加载减轻了N + 1查询问题。
因此，如果您这样做：
with()它已经加载了关系，但是让我们说您这样做：
$boxes = Box::with('BoxLocations')->get();
如果您有50个Box，则此循环将运行51个查询。
但是当您使用$boxes = Box::all();
foreach($boxes as $box)
{
echo box->boxlocation->name;
}
方法并渴望加载该关系时，此循环将仅运行2个查询。
您还可以使用Lazy Eager Loading来决定何时加载关系