如何向 SQLite 表添加 1300 行？
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【中文标题】如何向 SQLite 表添加 1300 行？【英文标题】：How to add 1300 rows to SQLite table? 【发布时间】：2021-09-23 13:57:38 【问题描述】：在 android Studio 中，我需要为城市和人口列表创建一个 SQLite 表。它大约有 1300 行。该列表位于 2 列 Excel 文件中，因此我可以将其从那里复制到我的代码中。
我有一个管理数据库的类和一个创建表的方法，但我不知道如何将城市人口列表添加到表中。
这是我必须创建表的代码部分：
String crearTablaCities = "CREATE TABLE "+MI_TABLA_CITIES+" (ID_CITY INTEGER PRIMARY KEY AUTOINCREMENT, NAME_CITY TEXT, POPULATION_CITY INTEGER)";
db.execSQL(crearTablaCities);
我知道如何添加一行从某处获取值，但我不知道如何自动添加超过 1300 行，这样我就不必手动编写或修改超过 1300 行。
public void insertCity(ObjectCity newCity)
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
//cv.put("ID_CITY", newCity.getCityID());
cv.put("NAME_CITY", newCity.getCityName());
cv.put("POPULATION_CITY", newCity.getCityPopulation());
db.insert(MI_TABLA_CITIES,null,cv);
//db.close();
我不知道如何面对下一步。有人可以给我一些提示以找到方法吗？提前非常感谢
【问题讨论】：
【参考方案1】：您可以通过 3 种相对简单的方法来完成此操作。
a) 创建一个代表您生成代码的公式，然后将生成的代码复制并粘贴到合适的位置。
b) 将数据保存为 csv 并将文件复制为资产，然后您可以打开并读取文件，提取数据并将其插入到数据库助手的 onCreate 方法中。
c) 将数据保存为 csv，并使用 SQLite 工具导入和加载数据，然后将该数据库复制为资产，然后使用该数据库。
选项A很简单，假设你有类似的东西：-
您的代码显示您有一个 insertCity 方法，该方法采用 City 对象。假设您使用City("Tokyo",37339804) 构建一个城市，然后插入一个城市，您的代码可能类似于：-
`insert(new ObjectCity("Tokyo",37339804L));`
然后您可以在单元格 C1 中输入一个公式为="insertCity(new ObjectCity("&CHAR(34)&A1&CHAR(34)&","&B1&"L));"。然后，您可以将此单元格复制到 c2-c1300（c2-c17 使用上面的电子表格）。生成的电子表格将如下所示：-
然后，您可以将生成的代码（单元格 c1-c1300）拖放复制并粘贴到合适的位置。
这是一个工作示例：-
ObjectCity 类：-
public class ObjectCity
private String cityName;
private Long cityPopulation;
public ObjectCity(String cityName, Long cityPopulation)
this.cityName = cityName;
this.cityPopulation = cityPopulation;
public String getCityName()
return cityName;
public Long getCityPopulation()
return cityPopulation;
public void setCityName(String cityName)
this.cityName = cityName;
public void setCityPopulation(Long cityPopulation)
this.cityPopulation = cityPopulation;
DatabaseHelper DBHelper 类（基于问题中的代码）：-
public class DBHelper extends SQLiteOpenHelper
public static final String MI_TABLA_CITIES = "city";
public DBHelper(Context context)
super(context, "theDatabase", null, 1);
@Override
public void onCreate(SQLiteDatabase db)
String crearTablaCities = "CREATE TABLE "+MI_TABLA_CITIES+" (ID_CITY INTEGER PRIMARY KEY AUTOINCREMENT, NAME_CITY TEXT, POPULATION_CITY INTEGER)";
db.execSQL(crearTablaCities);
@Override
public void onUpgrade(SQLiteDatabase db, int i, int i1)
public void insertCity(ObjectCity newCity)
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
//cv.put("ID_CITY", newCity.getCityID());
cv.put("NAME_CITY", newCity.getCityName());
cv.put("POPULATION_CITY", newCity.getCityPopulation());
db.insert(MI_TABLA_CITIES,null,cv);
//db.close();
/* function to load the country data */
public void loadData()
if(DatabaseUtils.queryNumEntries(this.getWritableDatabase(),MI_TABLA_CITIES)> 0) return;
insertCity(new ObjectCity("Tokyo",37339804L));
insertCity(new ObjectCity("Delhi",31181376L));
insertCity(new ObjectCity("Shanghai",27795702L));
insertCity(new ObjectCity("Sao Paulo",22237472L));
insertCity(new ObjectCity("Mexico City",21918936L));
insertCity(new ObjectCity("Dhaka",21741090L));
insertCity(new ObjectCity("Cairo",21322750L));
insertCity(new ObjectCity("Beijing",20896820L));
insertCity(new ObjectCity("Mumbai",20667656L));
insertCity(new ObjectCity("Osaka",19110616L));
insertCity(new ObjectCity("Karachi",16459472L));
insertCity(new ObjectCity("Chongqing",16382376L));
insertCity(new ObjectCity("Istanbul",15415197L));
insertCity(new ObjectCity("Buenos Aires",15257673L));
insertCity(new ObjectCity("Kolkata",14974073L));
insertCity(new ObjectCity("Kinshasa",14970460L));
insertCity(new ObjectCity("Lagos",14862111L));
注意 loadData 方法。
最后一个调用活动 MainActivity :-
public class MainActivity extends AppCompatActivity
DBHelper db;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
db = new DBHelper(this);
db.loadData(); //<<<<< LOADS THE CITY DATA (if not already loaded)
结果
运行上述程序并使用 Android Studio 的 Database Inspector 显示：-
【讨论】：
【参考方案2】：从第一个答案开始：-
c) 将数据保存为 csv，并使用 SQLite 工具导入和加载数据，然后将该数据库复制为资产，然后使用该数据库。
然后使用 Excel 保存原始工作表的 csv。这是导入到 SQLite 的 SQLite 工具 Navicat for SQLite（还有其他这样的工具，但我更喜欢 Navicat）：-
数据库和连接已关闭（保存数据库）。
在Android studio中，App在Android View中被右键点击New然后Directory被选中（单击）并从对话框中选择了 src/Android/assets（也就是在 app/src/main 中创建了 assets 文件夹（可以在 Android Studio 之外完成））。
数据库文件（名为 thedatabase.db）已复制到新创建的资产文件夹中。
Database Helper 类 DBHelperB 是按照以下方式编写的：-
public class DBHelperB extends SQLiteOpenHelper
/*
Note database created in SQLite tool and data imported from spreadsheet
database file is the copied into the assets folder (after creating the folder)
*/
public static final String DBNAME = "thedatabase.db"; //<<<< asset file name must match
public static final String MI_TABLA_CITIES = "city";
private static volatile DBHelperB instance = null;
// Prevent construction outside
private DBHelperB(Context context)
super(context, "theDatabase", null, 1);
// instead of using db = new DBHelper(this);
// this allows db = DBHelperB.getInstance();
// i.e. a single instance (aka a singleton) is retrieved
// IMPORTANTLY this also copies the asset DB if not already loaded
public static DBHelperB getDBInstance(Context context)
if (instance == null)
getAssetDB(context); // <<<<< Copies ASSET DB
instance = new DBHelperB(context);
return instance;
/* Won't be called as the DB will exists */
@Override
public void onCreate(SQLiteDatabase db)
String crearTablaCities = "CREATE TABLE "+MI_TABLA_CITIES+" (ID_CITY INTEGER PRIMARY KEY AUTOINCREMENT, NAME_CITY TEXT, POPULATION_CITY INTEGER)";
db.execSQL(crearTablaCities);
@Override
public void onUpgrade(SQLiteDatabase db, int i, int i1)
public void insertCity(ObjectCity newCity)
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
//cv.put("ID_CITY", newCity.getCityID());
cv.put("NAME_CITY", newCity.getCityName());
cv.put("POPULATION_CITY", newCity.getCityPopulation());
db.insert(MI_TABLA_CITIES,null,cv);
//db.close();
/*
Copies the DB from the assets folder unless the db already exists
Note if this fails a runtime exception will occur. It is then
IMPORTANT to look at the log to determine the cause
More often than not a failure is due to the asset not having been copied correctly
*/
private static void getAssetDB(Context context)
File dbFile = context.getDatabasePath(DBNAME);
InputStream asset;
OutputStream db;
byte[] buffer = new byte[4096];
if (dbFile.exists()) return; // Database exists so no need to copy
/* Ensure that the data/data/<package_name>/databases folder exists */
if (!dbFile.getParentFile().exists())
dbFile.getParentFile().mkdirs();
try
asset = context.getAssets().open(DBNAME);
db = new FileOutputStream(dbFile);
int length;
while ((length = asset.read(buffer)) > 0)
db.write(buffer,0,length);
db.flush();
db.close();
asset.close();
catch (Exception e)
e.printStackTrace();
throw new RuntimeException("Failed to copy asset file");
MainActivity 随后被修改为：-
public class MainActivity extends AppCompatActivity
DBHelper db;
DBHelperB assetdb; //ADDED
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
db = new DBHelper(this);
db.loadData();
// ADDED >
assetdb = DBHelperB.getDBInstance(this); /* will copy the asset db if need be */
/* Database inspector doesn't like this data so show data another way */
Cursor csr = assetdb.getWritableDatabase().query("city",null,null,null,null,null,null);
DatabaseUtils.dumpCursor(csr);
运行后的结果，根据日志包括：-
2021-07-15 09:16:54.454 I/System.out: >>>>> Dumping cursor android.database.sqlite.SQLiteCursor@374559d
2021-07-15 09:16:54.455 I/System.out: 0
2021-07-15 09:16:54.455 I/System.out: ID_CITY=1
2021-07-15 09:16:54.455 I/System.out: NAME_CITY=Tokyo
2021-07-15 09:16:54.455 I/System.out: POPULATION_CITY=37339804
2021-07-15 09:16:54.455 I/System.out:
2021-07-15 09:16:54.455 I/System.out: 1
2021-07-15 09:16:54.456 I/System.out: ID_CITY=2
2021-07-15 09:16:54.456 I/System.out: NAME_CITY=Delhi
2021-07-15 09:16:54.456 I/System.out: POPULATION_CITY=31181376
2021-07-15 09:16:54.456 I/System.out:
2021-07-15 09:16:54.456 I/System.out: 2
2021-07-15 09:16:54.456 I/System.out: ID_CITY=3
2021-07-15 09:16:54.456 I/System.out: NAME_CITY=Shanghai
2021-07-15 09:16:54.456 I/System.out: POPULATION_CITY=27795702
2021-07-15 09:16:54.456 I/System.out:
....
【讨论】：
惊人的答案！解释得很好，很完整，很有用！它对我有很大帮助！非常感谢！！以上是关于如何向 SQLite 表添加 1300 行？的主要内容，如果未能解决你的问题，请参考以下文章