tpt kids

common, and the different times are saved separately in separate instructor and Student tables. The schema for each entity class corresponding to a database table is called the Type Table TPT Inheritance (table per type). In the EF, TPH inheritance has better performance than TPT inheritance, because TPT inheritance requires complex connection queries. This t

There are several ways to map an inheritance relationship to a database table:First: TPH (table-per-hiaerachy) one table per level (only one table)Only a table with the name of a type named the parent class that contains all the property information for each subclass, using the Disciriminator column (usually the type name of the subclass), distinguishes which row represents what type of data.Second: TPT (table-per-type) Each type has a table (the pare

the header, that isNS. Common examples include: NSLog NSString NSInteger NSURL NSImage ... You will often see that some of the teaching will use: Nslog (@ "% d", Myint ); This statement is mainly used in the console for tracking. You will see the value of Myint in the console (open the dbg window when running in xcode ). In other development environments, we may prefer to use MessageBox for debugging. You can also see other classes with names, such as CF, CA, CG, and ui, such Cfstringtokenizer

yourself. Question 2: # What do import, @ interface, and so on? 1. # Import You can think of it as # include. But it is best to use # import. Remember this. 2. @ interface and so on For example, you can write a definition for the Child grabbing class in C: Public class kids: System { Private string kidname = "mykid "; Private string kidage = "15 "; Private bool iscaughtkid () { Return true; } } Of course, the above statement is not necessarily

follows:#include #include #include #define MAX_NUM 10typedef struct JUMP_KID{int num;int value;int pri;}jump_kid;int max_of_three (int a,int b,int c){/* Premises a!=b!=c*/int max3;if (a > B a > C)Max3 = A;else if (b > a b > C)Max3 = b;ElseMax3 = C;return max3;}int Comp_kids_value (const void *a, const void *b){//value Descending sortReturn (((Jump_kid *) b)->value-((Jump_kid *) a)->value);}int comp_kids_num (const void *a, const void *b){Return (((Jump_kid *) a)->num-(((Jump_kid *) b)->num);}

QueueDescriptionlinda is a teacher in ACM kindergarten. She is in charge of N kids. Because The dinning hall is a little bit far away from the classroom, those n kids has to walk in line to the dinning HAL L every day. When they is walking in line, if and only if the kids can see the other, they'll talk to each of the other. The

. @ interface and so on For example, you can write a definition for the Child grabbing class in C: Public class kids: System { Private string kidname = "mykid "; Private string kidage = "15 "; Private bool iscaughtkid () { Return true; } } Of course, the above statement is not necessarily correct. It is an example of a syntax. In objective-C, you have to write the following: First, write a kids. h file

POJ 3934 Queue DescriptionLinda is a teacher in ACM kindergarten. she is in charge of n kids. because the dinning hall is a little bit far away from the classroom, those n kids have to walk in line to the dinning hall every day. when they are walking in line, if and only if two kids can see each other, they will talk to each other. two

examples include:NslogNsstringNsintegerNsurlNsimage... You will often see that some of the teaching will use:Nslog (@ "% d", Myint ); This statement is mainly used in the console for tracking. You will see the value of Myint in the console (open the dbg window when running in xcode ). In other development environments, we may prefer to use MessageBox for debugging. You can also see other classes with names, such as CF, CA, CG, and ui, suchCfstringtokenizerCalayer, which indicates the layer of c

In JavaScript, object and array are passed by reference. Sometimes you may come into trouble if you don't keep this in mind, especial inRecursion. Let's see an example: First, prepare a JavaScript array to present a tree data: VaR treedata = [{"name": "root1", "kids": [{"name": "leaf1" },{ "name": "leaf2"}]}, {"name": "root2"}]; The expected HTML structure is: Our JavaScript code: Function resolvetree (rootnode,

object level (especially when autodetectchanges is disabled to improve dbcontext find () performance), available caches include query plan caching and metadata caching) and result cache (results caching ). EF still does not provide secondary cache, but we can refer to some guidelines for implementation-such as examples on codeplex and Julia Lerman'sArticle"Entity Framework and level 2 cache in Windows azure "; Optional no trace query (no State tracing overhead ). Currently, this option is on

of a class, including inherited, are mapped to columns in the corresponding table, which is known as a table (Table-per-concrete Class) inheritance for each specific class. If you implement TPC inheritance for the Person,student and instructor classes, then the student and instructor tables will be no different from the previous one.The TPC and TPH inheritance patterns in the Entity Framework are generally better than the TPT inheritance pattern beca

above, you can also see other classes with names, such as CF, CA, CG, and UI:For example:CFStringTokenizer is used for word segmentation.CALayer, which indicates the layer of Core AnimationCGPoint indicates a vertex.UIImage indicates the image in the iPhone.Break down the abbreviations:CF refers to Core Foundation, CA refers to Core Animation, CG refers to Core Graphics, and UI refers to Iphone UUser Interface .......Next, let's take a look at # import, @ interface,Of course, for example, # imp

. Table per type Clearly align with table You need to use a single query to find all sub-object objects. Different from TPH, you can set the table constraint for each type of variance. It is easy to change or adjust each type of data. When you want to obtain data from a single instance, You need to perform multiple join operations. The number of tables increases rapidly with the number of different types.

()) { context.Lodgings.Add(lodging); context.Lodgings.Add(resort); context.SaveChanges(); } We can see that EF uses discriminator to distinguish lodging from resort.Use fluent API to customize TPH delimiter Fields If you think that the default discriminator column name is not intuitive enough, you can use the fluent API to configure the type and name of the discriminator column (Data annotations are not marked and can be used to