数据库应用程序会导致崩溃 [英] Database causes app to crash
本文介绍了数据库应用程序会导致崩溃的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我试图与数据库的简单的应用程序。
问题是,由于某种原因,应用程序启动时崩溃。
可悲的是崩溃日志并没有告诉我很多,只是似乎有创建数据库的一个问题,但也许这里有人能理解它。
在此先感谢!
MainActivity
包se.welove code.wdmmg;进口android.support.v7.app.ActionBarActivity;
进口android.os.Bundle;
进口android.text.format.Time;
进口android.view.Menu;
进口android.view.MenuItem;
进口android.view.View;
进口android.widget.EditText;
公共类MainActivity扩展ActionBarActivity {DBAdapter MYDB;
的EditText etTransaction;@覆盖
保护无效的onCreate(捆绑savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.activity_main); openDB();
}保护无效的onDestroy(){
super.onDestroy();
closeDb();
}私人无效openDB(){
MYDB =新DBAdapter(本);
myDB.open();
}
私人无效closeDb(){ myDB.close();
}公共无效onClick_AddRecord(视图v){
myDB.insertRow(交易,项,总和);
}
}
DBAdapter
包se.welove code.wdmmg;进口android.content.ContentValues;
进口android.content.Context;
进口android.database.Cursor;
进口android.database.sqlite.SQLiteDatabase;
进口android.database.sqlite.SQLiteOpenHelper;
进口android.util.Log;公共类DBAdapter {私有静态最后弦乐TAG =DBAdapter; //用于记录数据库版本的变化//字段名称:
公共静态最后弦乐KEY_ROWID =_id;
公共静态最后弦乐KEY_TRANSACTION =交易;
公共静态最后弦乐KEY_ITEM =项;
公共静态最后弦乐KEY_SUM =总和;公共静态最后的String [] = ALL_KEYS新的String [] {KEY_ROWID,KEY_TRANSACTION,KEY_ITEM,KEY_SUM,};//为每个字段名称列数:
公共静态最终诠释COL_ROWID = 0;
公共静态最终诠释COL_TRANSACTION = 1;
公共静态最终诠释COL_ITEM = 2;
公共静态最终诠释COL_SUM = 3;//数据库信息:
公共静态最后弦乐DATABASE_NAME =DB;
公共静态最后弦乐DATABASE_TABLE =mainTransactions;
公共静态最终诠释DATABASE_VERSION = 1; //版本号必须每次更改数据库的结构发生时间递增。// SQL语句来创建数据库
私有静态最后弦乐DATABASE_CREATE_SQL =
CREATE TABLE+ DATABASE_TABLE
+(+ KEY_ROWID +INTEGER PRIMARY KEY AUTOINCREMENT
+ KEY_TRANSACTION +TEXT NOT NULL,
+ KEY_ITEM +TEXT NOT NULL,
+ KEY_SUM +TEXT
+);;私人最终上下文的背景下;
私人DatabaseHelper myDBHelper;
私人SQLiteDatabase分贝;
公共DBAdapter(上下文CTX){
this.context = CTX;
myDBHelper =新DatabaseHelper(背景);
}//打开数据库连接。
公共DBAdapter的open(){
DB = myDBHelper.getWritableDatabase();
返回此;
}//关闭数据库连接。
公共无效的close(){
myDBHelper.close();
}//添加一组新值的将被插入到数据库中。
众长的insertRow(字符串交易,项目字符串,字符串相加){
ContentValues initialValues =新ContentValues();
initialValues.put(KEY_TRANSACTION,交易);
initialValues.put(KEY_ITEM,项目);
initialValues.put(KEY_SUM,总和); //将数据存入数据库。
返回db.insert(DATABASE_TABLE,空,initialValues);
}//从数据库中删除一行,由ROWID(主键)
公共布尔deleteRow(长ROWID){
字符串,其中= KEY_ROWID +=+ ROWID;
返回db.delete(DATABASE_TABLE,其中,NULL)!= 0;
}公共无效deleteAll(){
光标C = getAllRows();
长ROWID = c.getColumnIndexOrThrow(KEY_ROWID);
如果(c.moveToFirst()){
做{
deleteRow(c.getLong((int)的ROWID));
}而(c.moveToNext());
}
c.close();
}//返回数据库中的所有数据。
公共光标getAllRows(){
字符串,其中= NULL;
光标C = db.query(真,DATABASE_TABLE,ALL_KEYS,其中,NULL,NULL,NULL,NULL,NULL);
如果(C!= NULL){
c.moveToFirst();
}
返回℃;
}//获取特定的行(由ROWID)
公共光标的getRow(长ROWID){
字符串,其中= KEY_ROWID +=+ ROWID;
光标C = db.query(真,DATABASE_TABLE,ALL_KEYS,
在这里,NULL,NULL,NULL,NULL,NULL);
如果(C!= NULL){
c.moveToFirst();
}
返回℃;
}//改变现有的行等于新的数据。
公共布尔updateRow(长ROWID,成交字符串,字符串项,字符串和){
字符串,其中= KEY_ROWID +=+ ROWID;
ContentValues newValues =新ContentValues();
newValues.put(KEY_TRANSACTION,交易);
newValues.put(KEY_ITEM,项目);
newValues.put(KEY_SUM,总和);
//把它插入到数据库中。
返回db.update(DATABASE_TABLE,newValues,其中,NULL)!= 0;
}
私有静态类DatabaseHelper扩展SQLiteOpenHelper
{
DatabaseHelper(上下文的背景下){
超(背景下,DATABASE_NAME,空,DATABASE_VERSION);
} @覆盖
公共无效的onCreate(SQLiteDatabase _db){
_db.execSQL(DATABASE_CREATE_SQL);
} @覆盖
公共无效onUpgrade(SQLiteDatabase _db,诠释oldVersion,诠释静态网页){
Log.w(TAG,从版本升级应用程序的数据库+ oldVersion
+到+ NEWVERSION +,这将销毁所有旧的数据!); //销毁旧的数据库:
_db.execSQL(DROP TABLE IF EXISTS+ DATABASE_TABLE); //重新创建新的数据库:
的onCreate(_db);
}
}
}
崩溃日志
了java.lang.RuntimeException:无法启动活动ComponentInfo {se.welove code.wdmmg / se.welove code.wdmmg.MainActivity}:android.database .sqlite.SQLiteException:近交易:语法错误(code 1),在编译:CREATE TABLE mainTransactions(_id INTEGER PRIMARY KEY AUTOINCREMENT,交易文本NOT NULL,项目文本NOT NULL,TEXT总和,);
在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2814)
在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
在android.app.ActivityThread.access $ 900(ActivityThread.java:182)
在android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1475)
在android.os.Handler.dispatchMessage(Handler.java:102)
在android.os.Looper.loop(Looper.java:145)
在android.app.ActivityThread.main(ActivityThread.java:6141)
在java.lang.reflect.Method.invoke(本机方法)
在java.lang.reflect.Method.invoke(Method.java:372)
在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:1399)
在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
android.database.sqlite.SQLiteException:引起附近的交易:语法错误(code 1),在编译:CREATE TABLE mainTransactions(_id INTEGER PRIMARY KEY AUTOINCREMENT,交易文本NOT NULL,项目文本NOT NULL,总之TEXT,);
在android.database.sqlite.SQLiteConnection.native prepareStatement(本机方法)
在android.database.sqlite.SQLiteConnection.acquire preparedStatement(SQLiteConnection.java:1093)
在android.database.sqlite.SQLiteConnection。prepare(SQLiteConnection.java:670)
在android.database.sqlite.SQLiteSession。prepare(SQLiteSession.java:588)
在android.database.sqlite.SQLiteProgram<&初始化GT;(SQLiteProgram.java:59)
在android.database.sqlite.SQLiteStatement<&初始化GT;(SQLiteStatement.java:31)
在android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1798)
在android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1729)
在se.welove code.wdmmg.DBAdapter $ DatabaseHelper.onCreate(DBAdapter.java:132)
在android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:251)
在android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
在se.welove code.wdmmg.DBAdapter.open(DBAdapter.java:54)
在se.welove code.wdmmg.MainActivity.openDB(MainActivity.java:32)
在se.welove code.wdmmg.MainActivity.onCreate(MainActivity.java:22)
在android.app.Activity.performCreate(Activity.java:6374)
在android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2767)
在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
在android.app.ActivityThread.access $ 900(ActivityThread.java:182)
在android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1475)
在android.os.Handler.dispatchMessage(Handler.java:102)
在android.os.Looper.loop(Looper.java:145)
在android.app.ActivityThread.main(ActivityThread.java:6141)
在java.lang.reflect.Method.invoke(本机方法)
在java.lang.reflect.Method.invoke(Method.java:372)
在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:1399)
在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
解决方案
您去错在这里。
从上 + KEY_SUM +TEXT,//去掉,(逗号)
正确的:
字符串DATABASE_CREATE_SQL =
CREATE TABLE+ DATABASE_TABLE
+(+ KEY_ROWID +INTEGER PRIMARY KEY AUTOINCREMENT
+ KEY_TRANSACTION +TEXT NOT NULL,
+ KEY_ITEM +TEXT NOT NULL,
+ KEY_SUM +TEXT
+);;
同样改变的交易列名becoz它的保留,不能在查询中使用。
I'm trying to make a simple app with a database. The problem is that for some reason the app crashes upon launch. Sadly the crash log doesn't tell me very much except that there seems to be a problem to create the database, but maybe someone here can understand it. Thanks in advance!
MainActivity
package se.welovecode.wdmmg;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.text.format.Time;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends ActionBarActivity {
DBAdapter myDB;
EditText etTransaction;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
openDB();
}
protected void onDestroy(){
super.onDestroy();
closeDb();
}
private void openDB(){
myDB = new DBAdapter(this);
myDB.open();
}
private void closeDb(){
myDB.close();
}
public void onClick_AddRecord(View v){
myDB.insertRow("transaction","item","sum");
}
}
DBAdapter
package se.welovecode.wdmmg;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter {
private static final String TAG = "DBAdapter"; //used for logging database version changes
// Field Names:
public static final String KEY_ROWID = "_id";
public static final String KEY_TRANSACTION = "transaction";
public static final String KEY_ITEM = "item";
public static final String KEY_SUM = "sum";
public static final String[] ALL_KEYS = new String[] {KEY_ROWID, KEY_TRANSACTION, KEY_ITEM, KEY_SUM,};
// Column Numbers for each Field Name:
public static final int COL_ROWID = 0;
public static final int COL_TRANSACTION = 1;
public static final int COL_ITEM = 2;
public static final int COL_SUM = 3;
// DataBase info:
public static final String DATABASE_NAME = "db";
public static final String DATABASE_TABLE = "mainTransactions";
public static final int DATABASE_VERSION = 1; // The version number must be incremented each time a change to DB structure occurs.
//SQL statement to create database
private static final String DATABASE_CREATE_SQL =
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_TRANSACTION + " TEXT NOT NULL, "
+ KEY_ITEM + " TEXT NOT NULL, "
+ KEY_SUM + " TEXT,"
+ ");";
private final Context context;
private DatabaseHelper myDBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx) {
this.context = ctx;
myDBHelper = new DatabaseHelper(context);
}
// Open the database connection.
public DBAdapter open() {
db = myDBHelper.getWritableDatabase();
return this;
}
// Close the database connection.
public void close() {
myDBHelper.close();
}
// Add a new set of values to be inserted into the database.
public long insertRow(String transaction, String item, String sum) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_TRANSACTION, transaction);
initialValues.put(KEY_ITEM, item);
initialValues.put(KEY_SUM, sum);
// Insert the data into the database.
return db.insert(DATABASE_TABLE, null, initialValues);
}
// Delete a row from the database, by rowId (primary key)
public boolean deleteRow(long rowId) {
String where = KEY_ROWID + "=" + rowId;
return db.delete(DATABASE_TABLE, where, null) != 0;
}
public void deleteAll() {
Cursor c = getAllRows();
long rowId = c.getColumnIndexOrThrow(KEY_ROWID);
if (c.moveToFirst()) {
do {
deleteRow(c.getLong((int) rowId));
} while (c.moveToNext());
}
c.close();
}
// Return all data in the database.
public Cursor getAllRows() {
String where = null;
Cursor c = db.query(true, DATABASE_TABLE, ALL_KEYS, where, null, null, null, null, null);
if (c != null) {
c.moveToFirst();
}
return c;
}
// Get a specific row (by rowId)
public Cursor getRow(long rowId) {
String where = KEY_ROWID + "=" + rowId;
Cursor c = db.query(true, DATABASE_TABLE, ALL_KEYS,
where, null, null, null, null, null);
if (c != null) {
c.moveToFirst();
}
return c;
}
// Change an existing row to be equal to new data.
public boolean updateRow(long rowId, String transaction, String item, String sum) {
String where = KEY_ROWID + "=" + rowId;
ContentValues newValues = new ContentValues();
newValues.put(KEY_TRANSACTION, transaction);
newValues.put(KEY_ITEM, item);
newValues.put(KEY_SUM, sum);
// Insert it into the database.
return db.update(DATABASE_TABLE, newValues, where, null) != 0;
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase _db) {
_db.execSQL(DATABASE_CREATE_SQL);
}
@Override
public void onUpgrade(SQLiteDatabase _db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading application's database from version " + oldVersion
+ " to " + newVersion + ", which will destroy all old data!");
// Destroy old database:
_db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
// Recreate new database:
onCreate(_db);
}
}
}
Crash log
java.lang.RuntimeException: Unable to start activity ComponentInfo{se.welovecode.wdmmg/se.welovecode.wdmmg.MainActivity}: android.database.sqlite.SQLiteException: near "transaction": syntax error (code 1): , while compiling: CREATE TABLE mainTransactions (_id INTEGER PRIMARY KEY AUTOINCREMENT, transaction TEXT NOT NULL, item TEXT NOT NULL, sum TEXT,);
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2814)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access$900(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: android.database.sqlite.SQLiteException: near "transaction": syntax error (code 1): , while compiling: CREATE TABLE mainTransactions (_id INTEGER PRIMARY KEY AUTOINCREMENT, transaction TEXT NOT NULL, item TEXT NOT NULL, sum TEXT,);
at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:1093)
at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:670)
at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:59)
at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1798)
at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1729)
at se.welovecode.wdmmg.DBAdapter$DatabaseHelper.onCreate(DBAdapter.java:132)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:251)
at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
at se.welovecode.wdmmg.DBAdapter.open(DBAdapter.java:54)
at se.welovecode.wdmmg.MainActivity.openDB(MainActivity.java:32)
at se.welovecode.wdmmg.MainActivity.onCreate(MainActivity.java:22)
at android.app.Activity.performCreate(Activity.java:6374)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2767)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access$900(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
解决方案
You go wrong here
+ KEY_SUM + " TEXT," // remove ,(comma) from last
correct:
String DATABASE_CREATE_SQL =
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_TRANSACTION + " TEXT NOT NULL, "
+ KEY_ITEM + " TEXT NOT NULL, "
+ KEY_SUM + " TEXT"
+ ");";
Also change transaction column name becoz it's reserved and cannot be used in queries.
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