iOS: 学习笔记, 使用FMDatabase操作sqlite3
使用FMDatabase操作sqlite3数据库非常简单和方便
1 // 2 // main.m 3 // iOSDemo0602_sqlite3 4 // 5 // Created by yao_yu on 14-6-2. 6 // Copyright (c) 2014年 yao_yu. All rights reserved. 7 // 8 9 #import <UIKit/UIKit.h> 10 #import "FMDatabase.h" 11 12 void test01(); 13 BOOL isfile(NSString *path); 14 BOOL isdir(NSString *path); 15 16 int main(int argc, char * argv[]) 17 { 18 @autoreleasepool { 19 test01(); 20 } 21 return 0; 22 } 23 24 void test01() 25 { 26 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentationDirectory, NSUserDomainMask, YES); 27 NSString *docpath = [paths objectAtIndex:0]; 28 NSString *dbpath = [docpath stringByAppendingPathComponent:@"YY/Data2"]; 29 // NSLog(@"%@", dbpath); 30 if (!isdir(dbpath)) { 31 NSFileManager *fileManager = [NSFileManager defaultManager]; 32 [fileManager createDirectoryAtPath:dbpath withIntermediateDirectories:YES attributes:nil error:nil]; 33 } 34 35 NSString *dbfile = [dbpath stringByAppendingPathComponent:@"data.db"]; 36 NSLog(@"%@", dbfile); 37 38 //初始化 39 FMDatabase *db = [FMDatabase databaseWithPath:dbfile]; 40 //打开数据库 41 [db open]; 42 43 //删除表 44 [db executeUpdate:@"drop table persons"]; 45 46 //添加表 47 [db executeUpdate:@"create table persons(id, name)"]; 48 49 //删除原有数据 50 [db executeUpdate:@"delete from persons"]; 51 52 //使用事务添加数据 53 [db beginTransaction]; 54 for(int i=0; i< 10000; i++) 55 { 56 [db executeUpdate:@"insert into persons values(?,?)", [NSString stringWithFormat:@"%d", i], [NSString stringWithFormat:@"第%d", i]]; 57 } 58 [db commit]; 59 60 //数据查询 61 FMResultSet *cursor = [db executeQuery:@"select * from persons"]; 62 int nCols = cursor.columnCount; 63 while ([cursor next]) { 64 for (int i=0; i<nCols; i++) { 65 printf("%s ", [[cursor stringForColumnIndex:i] UTF8String]); 66 } 67 printf("\n"); 68 } 69 cursor = nil; 70 71 //关闭数据库 72 [db close]; 73 74 //删除数据库测试文件 75 [[NSFileManager defaultManager] removeItemAtPath:dbfile error:nil]; 76 77 } 78 79 BOOL isfile(NSString *path) 80 { 81 NSFileManager *fileManager = [NSFileManager defaultManager]; 82 BOOL isdir = NO; 83 if ([fileManager fileExistsAtPath:path isDirectory: &isdir]) { 84 return isdir == NO; 85 } 86 return NO; 87 } 88 89 BOOL isdir(NSString *path) 90 { 91 NSFileManager *fileManager = [NSFileManager defaultManager]; 92 BOOL isdir = NO; 93 if ([fileManager fileExistsAtPath:path isDirectory: &isdir]) { 94 return isdir == YES; 95 } 96 return NO; 97 }
