CoreData基本操作CRUD 多表關(guān)聯(lián) 多個(gè)數(shù)據(jù)庫(kù)的操作

Demo鏈接

1、CoreData的基本操作CRUD
//
//  ViewController.m
//  ScutCoreData
//
//  Created by bwu on 16/5/19.
//  Copyright ? 2016年 wubiao. All rights reserved.
//

#import "ViewController.h"
#import "Student.h"
#import "Student+CoreDataProperties.h"
#include <CoreData/CoreData.h>

/*
    1.創(chuàng)建模型文件 [相當(dāng)于一個(gè)數(shù)據(jù)庫(kù)里的表]
    2.添加實(shí)體 [一張表]
    3.創(chuàng)建實(shí)體類(lèi) [相當(dāng)模型]
    4.生成上下文 關(guān)聯(lián)模型文件生成數(shù)據(jù)庫(kù)
    5、關(guān)聯(lián)的時(shí)候,如果本地沒(méi)有數(shù)據(jù)庫(kù)文件,Coreadata自己會(huì)創(chuàng)建
 */
@interface ViewController ()
@property(nonatomic,strong) NSManagedObjectContext *context;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    // .xcdatamodeld文件相當(dāng)于數(shù)據(jù)庫(kù)文件,里面的實(shí)體(Entity)即是"表",一個(gè)數(shù)據(jù)庫(kù)中可以有多張表格
    
    //1、創(chuàng)建上下文對(duì)象,對(duì)數(shù)據(jù)庫(kù)的所有操作都是通過(guò)對(duì)應(yīng)的上下文進(jìn)行操作的
    NSManagedObjectContext *context = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
    
    //2、實(shí)例化模型文件(數(shù)據(jù)庫(kù)文件)
    //mergedModelFromBundles這個(gè)方法傳入nil時(shí),會(huì)搜索工程項(xiàng)目中所有的.xcdatamodeld文件,并將這些文件中的所有表格放在一個(gè)數(shù)據(jù)庫(kù)。當(dāng)有多個(gè)數(shù)據(jù)庫(kù)時(shí)使用這個(gè)方法會(huì)造成數(shù)據(jù)的混亂
    NSManagedObjectModel *model = [NSManagedObjectModel mergedModelFromBundles:nil];
    
    
    //3、創(chuàng)建持久化存儲(chǔ)協(xié)調(diào)器,這個(gè)類(lèi)主要是關(guān)聯(lián)我的數(shù)據(jù)庫(kù)文件(模型文件\底層文件)
    NSPersistentStoreCoordinator *store = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
    
    //4、通過(guò)NSPersistentStoreCoordinator告訴Coredata數(shù)據(jù)庫(kù)的名字和路徑,并將它關(guān)聯(lián)上下文
    NSString *doc = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
    
    NSString *sqlitePath = [doc stringByAppendingPathComponent:@"student.sqlite"];
    NSLog(@"%@",sqlitePath);
    
    NSError *error = nil;
    [store addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:[NSURL fileURLWithPath:sqlitePath] options:nil error:&error];
    
    context.persistentStoreCoordinator = store; //上下文就是通過(guò)持久化存儲(chǔ)協(xié)調(diào)器來(lái)修改底層文件保存的數(shù)據(jù)
    self.context = context;
}


// 數(shù)據(jù)庫(kù)的操作 CURD Create Update  Read Delete
#pragma mark 添加學(xué)生
-(IBAction)addStudent{
    
    
    for (int i =0 ; i < 20; i++) {
        
 //通過(guò)NSEntityDescription向?qū)嶓w(表)中插入數(shù)據(jù),這個(gè)方法返回__kindof NSManagedObject *實(shí)體類(lèi)(模型Model)
        Student *student = [NSEntityDescription insertNewObjectForEntityForName:@"Student" inManagedObjectContext:self.context];
        //設(shè)置實(shí)體類(lèi)的相關(guān)屬性
        student.name =[NSString stringWithFormat:@"xiaoming%d",i];
        student.height = @1.80;
        student.brithday = [NSDate date];
        
        // 直接保存數(shù)據(jù)庫(kù)
        NSError *error = nil;
        [_context save:&error];
        
        if (error) {
            NSLog(@"%@",error);
        }
        
    }

    
    
    
 
}

#pragma mark 讀取學(xué)生信息
-(IBAction)readStudent{
    
    // 1.FectchRequest 抓取請(qǐng)求對(duì)象
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Student"];
    
    // 2.設(shè)置過(guò)濾條件
    // 查找zhangsan
    NSPredicate *pre = [NSPredicate predicateWithFormat:@"name = %@",
                        @"xiaoming1"];
     request.predicate = pre;
    
    // 3.設(shè)置排序
    // 身高的升序排序
    NSSortDescriptor *heigtSort = [NSSortDescriptor sortDescriptorWithKey:@"height" ascending:NO];
    request.sortDescriptors = @[heigtSort];
    
    
    // 4.執(zhí)行請(qǐng)求
    NSError *error = nil;
    
    NSArray *emps = [_context executeFetchRequest:request error:&error];
    if (error) {
        NSLog(@"error");
    }
    
    //NSLog(@"%@",emps);
    //遍歷員工
    for (Student *emp in emps) {
        NSLog(@"名字 %@ 身高 %@ 生日 %@",emp.name,emp.height,emp.brithday);
    }
    
}

#pragma mark 更新學(xué)生信息
-(IBAction)updateStudent{
    
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Student"];
    
    // 1.2設(shè)置過(guò)濾條件
    // 查找xiaoming2
    NSPredicate *pre = [NSPredicate predicateWithFormat:@"name = %@",
                        @"xiaoming2"];
    request.predicate = pre;
    
    // 1.3執(zhí)行請(qǐng)求
    NSArray *emps = [_context executeFetchRequest:request error:nil];
    
    
    // 2.更新身高
    for (Student *e in emps) {
        e.height = @2.0;
    }
    
    // 3.保存
    [_context save:nil];

}

#pragma mark 刪除學(xué)生
-(IBAction)deleteStudent{
    
    // 1.1FectchRequest 抓取請(qǐng)求對(duì)象
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Student"];
    
    // 1.2設(shè)置過(guò)濾條件
    // 查找xiaoming3
    NSPredicate *pre = [NSPredicate predicateWithFormat:@"name = %@",
                        @"xiaoming3"];
    request.predicate = pre;
    
    // 1.3執(zhí)行請(qǐng)求
    NSArray *emps = [_context executeFetchRequest:request error:nil];
    
    // 2.刪除
    for (Student *e in emps) {
        [_context deleteObject:e];
    }
    
    // 3.保存
    [_context save:nil];
    
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end
2、CoreData的多表進(jìn)行關(guān)聯(lián)
//
//  ViewController.m
//  ScutCoreData
//
//  Created by bwu on 16/5/19.
//  Copyright ? 2016年 wubiao. All rights reserved.
//

#import "ViewController.h"
#import "Student.h"
#import "Student+CoreDataProperties.h"
#import <CoreData/CoreData.h>
#import "Card.h"
#import "Card+CoreDataProperties.h"

/*
    1.創(chuàng)建模型文件 [相當(dāng)于一個(gè)數(shù)據(jù)庫(kù)里的表]
    2.添加實(shí)體 [一張表]
    3.創(chuàng)建實(shí)體類(lèi) [相當(dāng)模型]
    4.生成上下文 關(guān)聯(lián)模型文件生成數(shù)據(jù)庫(kù)
    5、關(guān)聯(lián)的時(shí)候,如果本地沒(méi)有數(shù)據(jù)庫(kù)文件,Coreadata自己會(huì)創(chuàng)建
 */
@interface ViewController ()
@property(nonatomic,strong) NSManagedObjectContext *context;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    // .xcdatamodeld文件相當(dāng)于數(shù)據(jù)庫(kù)文件,里面的實(shí)體(Entity)即是"表",一個(gè)數(shù)據(jù)庫(kù)中可以有多張表格
    
    //1、創(chuàng)建上下文對(duì)象,對(duì)數(shù)據(jù)庫(kù)的所有操作都是通過(guò)對(duì)應(yīng)的上下文進(jìn)行操作的
    NSManagedObjectContext *context = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
    
    //2、實(shí)例化模型文件(數(shù)據(jù)庫(kù)文件)
    //mergedModelFromBundles這個(gè)方法傳入nil時(shí),會(huì)搜索工程項(xiàng)目中所有的.xcdatamodeld文件,并將這些文件中的所有表格放在一個(gè)數(shù)據(jù)庫(kù)。當(dāng)有多個(gè)數(shù)據(jù)庫(kù)時(shí)使用這個(gè)方法會(huì)造成數(shù)據(jù)的混亂
    NSManagedObjectModel *model = [NSManagedObjectModel mergedModelFromBundles:nil];
    
    
    //3、創(chuàng)建持久化存儲(chǔ)協(xié)調(diào)器,這個(gè)類(lèi)主要是關(guān)聯(lián)我的數(shù)據(jù)庫(kù)文件(模型文件\底層文件)
    NSPersistentStoreCoordinator *store = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
    
    //4、通過(guò)NSPersistentStoreCoordinator告訴Coredata數(shù)據(jù)庫(kù)的名字和路徑,并將它關(guān)聯(lián)上下文
    NSString *doc = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
    
    NSString *sqlitePath = [doc stringByAppendingPathComponent:@"student.sqlite"];
    NSLog(@"%@",sqlitePath);
    
    NSError *error = nil;
    [store addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:[NSURL fileURLWithPath:sqlitePath] options:nil error:&error];
    
    context.persistentStoreCoordinator = store; //上下文就是通過(guò)持久化存儲(chǔ)協(xié)調(diào)器來(lái)修改底層文件保存的數(shù)據(jù)
    self.context = context;
}


// 數(shù)據(jù)庫(kù)的操作 CURD Create Update  Read Delete
#pragma mark 添加學(xué)生
-(IBAction)addStudent{
    
    
    for (int i =10 ; i < 20; i++) {
        
        
        
        Card *card = [NSEntityDescription insertNewObjectForEntityForName:@"Card" inManagedObjectContext:self.context];
        card.no = @"wubiao";
                
 //通過(guò)NSEntityDescription向?qū)嶓w(表)中插入數(shù)據(jù),這個(gè)方法返回__kindof NSManagedObject *實(shí)體類(lèi)(模型Model)
        Student *student = [NSEntityDescription insertNewObjectForEntityForName:@"Student" inManagedObjectContext:self.context];
        //設(shè)置實(shí)體類(lèi)的相關(guān)屬性
        student.name =[NSString stringWithFormat:@"xiaoming%d",i];
        student.height = @1.80;
        student.brithday = [NSDate date];
        // 設(shè)置Student和Card之間的關(guān)聯(lián)關(guān)系
        student.card = card;
        //card.student = student;

        // 直接保存數(shù)據(jù)庫(kù)
        NSError *error = nil;
        [_context save:&error];
        
        if (error) {
            NSLog(@"%@",error);
        }
        
    }
 
}

#pragma mark 讀取學(xué)生信息
-(IBAction)readStudent{
    
    // 1.FectchRequest 抓取請(qǐng)求對(duì)象
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Student"];
//    
//    // 2.設(shè)置過(guò)濾條件
//
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"card.no = %@",@"wubiao"];
     request.predicate = predicate;
    
    // 3.設(shè)置排序
    // 身高的升序排序
    NSSortDescriptor *heigtSort = [NSSortDescriptor sortDescriptorWithKey:@"height" ascending:NO];
    request.sortDescriptors = @[heigtSort];
    

    // 4.執(zhí)行請(qǐng)求
    NSError *error = nil;
    
    NSArray *emps = [_context executeFetchRequest:request error:&error];
    if (error) {
        NSLog(@"error");
    }
    
    //NSLog(@"%@",emps);
    //遍歷員工
    for (Student *emp in emps) {
        NSLog(@"名字 %@ 身高 %@ 生日 %@ 身份證號(hào)碼%@",emp.name,emp.height,emp.brithday,emp.card);
    }
    
}

#pragma mark 更新學(xué)生信息
-(IBAction)updateStudent{
    
 

}

#pragma mark 刪除學(xué)生
-(IBAction)deleteStudent{
 
    
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end


3、CoreData的多個(gè)數(shù)據(jù)庫(kù)的操作
/*
    1.創(chuàng)建模型文件 [相當(dāng)于一個(gè)數(shù)據(jù)庫(kù)里的表]
    2.添加實(shí)體 [一張表]
    3.創(chuàng)建實(shí)體類(lèi) [相當(dāng)模型]
    4.生成上下文 關(guān)聯(lián)模型文件生成數(shù)據(jù)庫(kù)
    5、關(guān)聯(lián)的時(shí)候,如果本地沒(méi)有數(shù)據(jù)庫(kù)文件,Coreadata自己會(huì)創(chuàng)建
 */
@interface ViewController ()
@property(nonatomic,strong) NSManagedObjectContext *context;
@property(nonatomic,strong) NSManagedObjectContext *studentContext;
@property(nonatomic,strong) NSManagedObjectContext *weiboContext;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    

    
    // 一個(gè)數(shù)據(jù)庫(kù)對(duì)應(yīng)一個(gè)上下文
    _studentContext = [self setupContextWithModelName:@"Student"];
    _weiboContext = [self setupContextWithModelName:@"Weibo"];
}



-(NSManagedObjectContext *)setupContextWithModelName:(NSString *)modelName
{
    // .xcdatamodeld文件相當(dāng)于數(shù)據(jù)庫(kù)文件,里面的實(shí)體(Entity)即是"表",一個(gè)數(shù)據(jù)庫(kù)中可以有多張表格
    
    //1、創(chuàng)建上下文對(duì)象,對(duì)數(shù)據(jù)庫(kù)的所有操作都是通過(guò)對(duì)應(yīng)的上下文進(jìn)行操作的
    NSManagedObjectContext *context = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
    
    //2、實(shí)例化模型文件(數(shù)據(jù)庫(kù)文件)
    //2.1mergedModelFromBundles這個(gè)方法傳入nil時(shí),會(huì)搜索工程項(xiàng)目中所有的.xcdatamodeld文件,并將這些文件中的所有表格放在一個(gè)數(shù)據(jù)庫(kù)。當(dāng)有多個(gè)數(shù)據(jù)庫(kù)時(shí)使用這個(gè)方法會(huì)造成數(shù)據(jù)的混亂
//    NSManagedObjectModel *model = [NSManagedObjectModel mergedModelFromBundles:nil];
 
    NSLog(@"%@",[[NSBundle mainBundle] bundlePath]);
    //2.2當(dāng)工程項(xiàng)目中有多個(gè)數(shù)據(jù)庫(kù)時(shí) 要使用這個(gè)方法來(lái)實(shí)例化模型文件。這樣可以將不同的數(shù)據(jù)庫(kù)分開(kāi),而且不同的數(shù)據(jù)庫(kù)對(duì)應(yīng)不同的上下文
    NSURL *companyURL = [[NSBundle mainBundle] URLForResource:modelName withExtension:@"momd"];
    NSManagedObjectModel *model = [[NSManagedObjectModel alloc] initWithContentsOfURL:companyURL];
    
    
    //3、創(chuàng)建持久化存儲(chǔ)協(xié)調(diào)器,這個(gè)類(lèi)主要是關(guān)聯(lián)我的數(shù)據(jù)庫(kù)文件(模型文件\底層文件)
    NSPersistentStoreCoordinator *store = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
    
    //4、通過(guò)NSPersistentStoreCoordinator告訴Coredata數(shù)據(jù)庫(kù)的名字和路徑,并將它關(guān)聯(lián)上下文
    NSString *doc = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
    
    NSString *sqliteName = [NSString stringWithFormat:@"%@.sqlite",modelName];
    NSString *sqlitePath = [doc stringByAppendingPathComponent:sqliteName];
    NSLog(@"%@",sqlitePath);
    
    NSError *error = nil;
    [store addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:[NSURL fileURLWithPath:sqlitePath] options:nil error:&error];
    
    context.persistentStoreCoordinator = store; //上下文就是通過(guò)持久化存儲(chǔ)協(xié)調(diào)器來(lái)修改底層文件保存的數(shù)據(jù)
    return context;
}


// 數(shù)據(jù)庫(kù)的操作 CURD Create Update  Read Delete
#pragma mark 添加學(xué)生
-(IBAction)addStudent{

 //通過(guò)NSEntityDescription向?qū)嶓w(表)中插入數(shù)據(jù),這個(gè)方法返回__kindof NSManagedObject *實(shí)體類(lèi)(模型Model)
    Student *student = [NSEntityDescription insertNewObjectForEntityForName:@"Student" inManagedObjectContext:_studentContext];
    //設(shè)置實(shí)體類(lèi)的相關(guān)屬性
    student.name =@"xiaoming";
    student.height = @1.80;
    student.brithday = [NSDate date];
    
    // 直接保存數(shù)據(jù)庫(kù)
    NSError *error = nil;
    [_studentContext save:&error];
    
    if (error) {
        NSLog(@"%@",error);
    }
 
    // 發(fā)微博
    Status *status =[NSEntityDescription insertNewObjectForEntityForName:@"Status" inManagedObjectContext:_weiboContext];
    status.text = @"畢業(yè),挺激動(dòng)";
    [_weiboContext save:nil];

}

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