sqlite3的使用

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1>添加sqlite3动态库：libsqlite3.dylib

2>导入头文件：#import<sqlite3.h>

3>利用C函数创建/打开数据库，编写SQL语句

 自定义一个类DataBaseHandle继承NSObject

#import <Foundation/Foundation.h>
#import "Strategy.h"
@interface DataBaseHandle : NSObject

+(DataBaseHandle *)sharedInstance;

//打开数据库
-(void)openDB;

//关闭数据库
-(void)closeDB;

//插入新的数据
-(void)insertNewModel:(NSString *)name Data:(NSData *)data;

//删除某个保存的数据
-(void)deleteModelWithName:(NSString *)name;

//获取某个保存的数据
-(NSData *)selectModelWithName:(NSString *)name;

//获取所有的数据
-(NSArray *)selectAllModel;

//判断数据是否被保存
-(BOOL)isLoadModelWithName:(NSString *)name;

@end

下面是m文件的实现：

DataBaseHandle.m

#import "DataBaseHandle.h"
#import <sqlite3.h>
@implementation DataBaseHandle

static DataBaseHandle * handle = nil;
+(DataBaseHandle *)sharedInstance
{
    
    if (handle == nil) {
        handle = [[DataBaseHandle alloc] init];
    }
    
    return handle;
}

static sqlite3 *db=nil;
//打开数据库
-(void)openDB
{
    if (db!=nil) {
        return;
    }
    
    //存放数据库的路径和文件
    NSString *path=NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES).lastObject;
    NSString *filePath=[path stringByAppendingPathComponent:@"Strategy.sqlite"];
    
  //  NSLog(@"db filePath=%@",filePath);
    
    //打开数据库
    int result=sqlite3_open([filePath UTF8String], &db);
    if (result==SQLITE_OK) {
        
     //   NSLog(@"打开数据库成功");
        
        NSString * createActivitySql = @"CREATE TABLE StrategyList (NAME TEXT PRIMARY KEY , data BLOB)";
        //执行sql语句
        sqlite3_exec(db, [createActivitySql UTF8String], NULL, NULL, NULL);
        
    }
}

//关闭数据库
-(void)closeDB
{
    int result=sqlite3_close(db);
    if (result==SQLITE_OK) {
        
     //   NSLog(@"关闭数据库成功");
        
        db=nil;
    }
}

//插入新的数据
-(void)insertNewModel:(NSString *)name Data:(NSData *)data
{
    [self openDB];
    
    sqlite3_stmt *stmt=nil;
    
    NSString *sql= @"insert into StrategyList (NAME,data) values (?,?)";
    
    //验证sql语句
    int result=sqlite3_prepare_v2(db, [sql UTF8String], -1, &stmt, nil);
    
    if (result==SQLITE_OK) {
        
        //绑定数据
        sqlite3_bind_text(stmt, 1, [name UTF8String], -1, nil);
        
        sqlite3_bind_blob(stmt, 2, [data bytes], (int)[data length], nil);
        
        sqlite3_step(stmt);
        
    }
    
    sqlite3_finalize(stmt);
    
}

//删除某个保存的数据
-(void)deleteModelWithName:(NSString *)name
{
    [self openDB];
    
    sqlite3_stmt *stmt=nil;
    
    NSString *sql= @"delete from StrategyList where NAME = ?";
    
    //验证sql语句
    int result=sqlite3_prepare_v2(db, [sql UTF8String], -1, &stmt, nil);
    
    if (result==SQLITE_OK) {
        
        //绑定数据
        sqlite3_bind_text(stmt, 1, [name UTF8String], -1, nil);
        
        sqlite3_step(stmt);
        
    }
    
    sqlite3_finalize(stmt);
    
}


//获取某个保存的数据
-(NSData *)selectModelWithName:(NSString *)name
{
    
    [self openDB];
    
    sqlite3_stmt * stmt = nil;
    
    NSString * sql = @"select data from StrategyList where NAME = ?";
    
    int result = sqlite3_prepare_v2(db, [sql UTF8String], -1, &stmt, NULL);
    
    NSData * data = nil;
    
    if (result == SQLITE_OK) {
        
        sqlite3_bind_text(stmt, 1, [name UTF8String], -1, NULL);
        
        if (sqlite3_step(stmt) == SQLITE_ROW) {
            
            //bytes length
            
            data = [NSData dataWithBytes:sqlite3_column_blob(stmt, 0) length:sqlite3_column_bytes(stmt, 0)];
            
        }
        
    }
    
    sqlite3_finalize(stmt);
    
    return data;
}

//获取所有的数据
-(NSArray *)selectAllModel
{
    [self openDB];
    
    sqlite3_stmt * stmt = nil;
    
    NSString * sql = @"select NAME from StrategyList";
    
    int result = sqlite3_prepare_v2(db, [sql UTF8String], -1, &stmt, NULL);
    
    NSMutableArray * travelArray = [NSMutableArray array];
    
    if (result == SQLITE_OK) {
        
        while (sqlite3_step(stmt) == SQLITE_ROW) {
            
            
            NSString * name = [NSString stringWithUTF8String:(const char *)sqlite3_column_text(stmt, 0)];
            
            [travelArray addObject:name];
        }
        
    }
    
    sqlite3_finalize(stmt);
    
    return travelArray;
    
}

//判断数据是否被保存
-(BOOL)isLoadModelWithName:(NSString *)name
{
    NSData * data = [self selectModelWithName:name];
    if (data == nil) {
        return NO;
    }
    
    return YES;
    
}

@end

sqlite3的使用

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原文地址：http://www.cnblogs.com/linxiu-0925/p/5404419.html