表:电影
mID title year director
101 Gone with the Wind 1939 Victor Fleming
102 Star Wars 1977 George Lucas
103 The Sound of Music 1965 Robert Wise
104 E.T. 1982 Steven Spielberg
105 Titanic 1997 James Cameron
106 Snow White 1937 <null>
107 Avatar 2009 James Cameron
108 Raiders of the Lost Ark 1981 Steven Spielberg
表:评级
rID mID stars ratingDate
201 101 2 2011-01-22
201 101 4 2011-01-27
202 106 4 <null>
203 103 2 2011-01-20
203 108 4 …嗨我想在xcode 4中的c ++项目中使用sqlite
现在我收到了这个错误
Ld/Users/jayb/Library/Developer/Xcode/DerivedData/EMS-bpigynlzjbrescadebhoiupqmtkg/Build/Products/Debug/EMS normal x86_64 cd/Users/jayb/Documents/Developement/EMS/EMS setenv MACOSX_DEPLOYMENT_TARGET 10.8 /Applications/Xcode.app/目录/开发人员/工具链/ XcodeDefault.xctoolchain/usr/bin/clang ++ -arch x86_64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk -L/Users/jayb/Library/Developer/Xcode/DerivedData/EMS-bpigynlzjbrescadebhoiupqmtkg/Build/Products/Debug -F/Users/jayb/Library/Developer/Xcode/DerivedData/EMS-bpigynlzjbrescadebhoiupqmtkg/Build/Products/Debug -filelist/Users/jayb /Library/Developer/Xcode/DerivedData/EMS-bpigynlzjbrescadebhoiupqmtkg/Build/Intermediates/EMS.build/Debug/EMS.build/Objects-normal/x86_64/EMS.LinkFileList -mmacosx-version-min = 10.8 -o/Users/jayb /库/开发商/ Xcode中/ DerivedData/EMS-bpigynlzjbrescadebhoiupqmtkg /编译/产品/调试/ EMS
体系结构x86_64的未定义符号:"_ sqlite3_close",引用自:main.o"_sqlite3_errmsg"中的_main,引用自:main.o中的_main"_sqlite3_open",引自:main.o中的_main ld:未找到符号对于体系结构x86_64 clang:错误:链接器命令失败,退出代码为1(使用-v查看调用)
我发现它可能是编译器选项-lsqlite3修复的链接器问题
但是,我如何在Xcode中添加该选项??????
我使用xcode 4.4上的"运行"按钮来编译我的项目.我没有在终端窗口编译.
这是我的代码
#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <sqlite3.h>
using namespace std;
int main()
{
sqlite3 *db;
int rc = sqlite3_open("EMSDB", &db);
if (rc) {
fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db));
exit(0);
}
else {
fprintf(stderr, "Opened Database successfully\n");
}
sqlite3_close(db); …我需要在“用户名”表上添加主键
我有3列：
userid int(10)
username char(20)
user char(50)
和主键设置在“用户名”字段，我用它作为外键链接到另一个表。现在我还需要在'userid'字段上添加主键...所以我尝试了：
alter table `usernames` drop primary key, add primary key(userid,username);
我得到一个错误的说法
ERROR 1553 (HY000): Cannot drop index 'PRIMARY":needed in a foreign key constraint
有什么可能的方法吗？
我在android SQLite中有一个表,我试图弄清楚如何重置KEY_ID,我读到:DELETE FROM tablename应该删除所有内容并将自动增量字段重置为0但是当我这样做时它只是删除数据.插入新记录后,自动增量会在删除之前从中断处继续.我已经实现了一个longitemclicklistner列表,它获取了位置,我想从列表中删除特定项目.这是我的代码
public void deleteContact(Contact contact) {
SQLiteDatabase db = this.getWritableDatabase();
getWritableDatabase().delete(TABLE_CONTACTS, KEY_ID + " = ?",
new String[] { String.valueOf(contact.getID()) } );
db.close();
}
这是代码 onlongclicklistner
public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
int pos, long id) {
// TODO Auto-generated method stub
Log.v("long clicked","pos"+" "+pos);
final int p=pos+1;
final AlertDialog.Builder b = new AlertDialog.Builder(MainActivity.this);
b.setIcon(android.R.drawable.ic_dialog_alert);
b.setMessage("Are you sure you want to DELETE this Entry?");
b.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface …我使用Xcode5在ios7上编码,编译器给我这个错误.
隐式转换失去整数精度
sqlite3_int64又名long long到int.
下面的代码如下:
if([self chatId] != nil) {
[chatId release];
}
chatId = [[NSNumber alloc] initWithInt:sqlite3_last_insert_rowid(database)];
sqlite3_finalize(sqlStatement);
有帮助吗？
我在我的主要活动类中有这个代码
public class HomeScreenActivity extends Activity {
private Button contactButton;
private Button groupContactButton;
private Button historyButton;
private Button optionsButton;
private ListView contactsView;
public static int selectedContactIndex = -1;
DatabaseHandler db = new DatabaseHandler(getApplicationContext());
List<Contact> contactList = db.getAllContacts();
ArrayAdapter<Contact> adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_screen);
contactButton = (Button) findViewById(R.id.contactButton);
contactButton.setSelected(true);
groupContactButton = (Button) findViewById(R.id.groupContactButton);
historyButton = (Button) findViewById(R.id.historyButton);
optionsButton = (Button) findViewById(R.id.optionsButton);
contactsView = (ListView) findViewById(R.id.contactsView);
// Set up contact adaptor so the contact list can be viewed …我以支持的格式(yyyy-mm-dd)在sqlite数据库中插入日期.现在我希望用户在查询时根据国家/地区显示日期格式(意大利dd-mm-yyyy,美国yyyy-mm-dd等...)
我如何能？谢谢
我在这里已经阅读了很多关于上述问题的线索/问题,但似乎没有任何解决方案对我有用.这是我的数据库创建:
public static final String TABLE_CARDS = "cards";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_QUESTION = "question";
public static final String COLUMN_ANSWER = "answer";
private static final String DATABASE_NAME = "cards.db";
private static final int DATABASE_VERSION = 1;
// Database creation sql statement
private static final String DATABASE_CREATE = "create table "
+ TABLE_CARDS + "("
+ COLUMN_ID + " integer primary key autoincrement, "
+ COLUMN_QUESTION + " text not null, "
+ COLUMN_ANSWER …我试图从非活动类加载SQLite数据库
我需要DBHelperAdapter类的上下文并使用ApplicationContextProvider如下所述的类.(我没有将这个添加到清单中,因为一些教程建议但是因为我不确定如何.)
CNYearsAdapter myCNYearsAdapter = new CNYearsAdapter( ApplicationContextProvider.getContext());
应用环境提供者:
package com.example.kuachart;
import android.app.Application;
import android.content.Context;
public class ApplicationContextProvider extends Application {
/**
* Keeps a reference of the application context
*/
private static Context sContext;
@Override
public void onCreate() {
super.onCreate();
sContext = getApplicationContext();
}
/**
* Returns the application context
*
* @return application context
*/
public static Context getContext() {
return sContext;
}
}
目前,实例化上面的行myCNYearsAdapter崩溃了程序,因此我不确定Application上下文提供程序是否正常工作.是否有另一种方法可以将上下文传递给此非活动类？
我相信错误在于我设置DATABASE_CREATE的方式.我在这里错过了什么吗？我得到SQLiteException,其中long id = -1.如果我提供足够的细节,请告诉我.我试过设置KEY_ID ="_ id";
E/SQLiteLog(2385): (1) near "group": syntax error
E/SQLiteDatabase(2385): Error inserting group=demo
E/SQLiteDatabase(2385): android.database.sqlite.SQLiteException: near "group": syntax error (code 1): , while compiling: INSERT INTO groups(group) VALUES (?)
LOG(2385): Inserting record...
LOG(2385): mGroupName = demo
LOG(2385): long id = -1
DBAdapter.java
public static final String KEY_ID = "id";
public static final String KEY_GROUP_NAME = "group";
public static final String TAG = "DBAdapter";
public static final String DATABASE_NAME = "GroupsDB";
public static final String DATABASE_TABLE = "groups"; …