唯一约束失败:sqlite 数据库:android

UNIQUE constraint failed: sqlite database : android

我正在尝试在 table 中插入值。但是只插入了一个值。当我尝试插入新值时,log cat 中出现错误。

日志猫显示:

abort at 13 in [INSERT INTO event(totalminutesfrom,dayofweek,title,location,totalminutesto,id) VALUES (?,?,?,?,?,?)]: UNIQUE constraint failed: event.id
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase: Error inserting totalminutesfrom=694 dayofweek=null title=qxs location=Eded & Mariz totalminutesto=0 id=0
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase: android.database.sqlite.SQLiteConstraintException: UNIQUE constraint failed: event.id (code 1555)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:782)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1471)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1341)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at com.example.siddhi.timetablelayout.EventTableHelper.addEvent(EventTableHelper.java:76)
01-24 11:34:39.764 7763-7763/com.example.siddhi.timetablelayout E/SQLiteDatabase:     at com.example.siddhi.timetablelayout.AddEventActivity.onClick(AddEventActivity.java:217)

插入行时这两行显示错误。

db.insert(TABLE, null, values);

   db.addEvent(new EventData(eventTitle,dayOfWeek,totalMinutesFrom, totalMinutesTo,location));

事件表助手

public class EventTableHelper extends SQLiteOpenHelper {


    private static final String TABLE = "event";
    private static final String KEY_ID = "id";
    private static final String KEY_TITLE = "title";
    private static final String KEY_LOCATION = "location";
    private static final String KEY_DAY_OF_WEEK = "dayofweek";
    private static final String KEY_TOTAL_MINUTES_FROM = "totalminutesfrom";
    private static final String KEY_TOTAL_MINUTES_TO = "totalminutesto";



    public EventTableHelper(Context context) {
        super(context, Constants.DATABASE_NAME, null, Constants.DATABASE_VERSION);
        //3rd argument to be passed is CursorFactory instance
    }

    // Creating Tables
    @Override
    public void onCreate(SQLiteDatabase db) {
        //createTable(db);
    }

    public void createTable(SQLiteDatabase db){
        String CREATE_EVENTS_TABLE = "CREATE TABLE " + TABLE + "("
                + KEY_ID + " INTEGER PRIMARY KEY," + KEY_TITLE + " TEXT,"
                + KEY_DAY_OF_WEEK +"TEXT" + KEY_TOTAL_MINUTES_FROM +"INTEGER"
                + KEY_TOTAL_MINUTES_TO + "INTEGER" +  KEY_LOCATION + "TEXT" +  ")";

        db.execSQL(CREATE_EVENTS_TABLE);

    }
    // Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Drop older table if existed
       // db.execSQL("DROP TABLE IF EXISTS " + TABLE);

      //  createTable(db);

        // Create tables again
        //onCreate(db);
    }

    // code to add the new contact
    public void addEvent(EventData event) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ID, event.getId());
        values.put(KEY_TITLE,event.getTitle()); // Contact Name
        values.put(KEY_DAY_OF_WEEK,event.getDayofWeek());
        values.put(KEY_TOTAL_MINUTES_FROM,event.getFromMinutes());
        values.put(KEY_TOTAL_MINUTES_TO,event.getToMinutes());
        values.put(KEY_LOCATION,event.getLocation());
        // Inserting Row
        db.insert(TABLE, null, values);
        //2nd argument is String containing nullColumnHack
        db.close(); // Closing database connection
    }

    // code to get the single contact
   EventData getEvent(int id) {
        SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE, new String[] { KEY_ID,
                        KEY_TITLE, KEY_DAY_OF_WEEK, KEY_TOTAL_MINUTES_FROM,KEY_TOTAL_MINUTES_TO,KEY_LOCATION }, KEY_ID + "=?",
                new String[] { String.valueOf(id) }, null, null, null, null);
        if (cursor != null)
            cursor.moveToFirst();
       EventData eventData = new EventData(Integer.parseInt(cursor.getString(0)),cursor.getString(1), cursor.getString(2),
               cursor.getInt(3),cursor.getInt(4),cursor.getString(5));

        return eventData;
    }



    // code to get all contacts in a list view
    public List<EventData> getAllEvents() {
        List<EventData> conList = new ArrayList<EventData>();
        // Select All Query
        String selectQuery = "SELECT  * FROM " + TABLE;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {

                EventData event = new EventData();

                event.setId(Integer.parseInt(cursor.getString(0)));
                event.setTitle(cursor.getString(1));
                event.setDayofWeek(cursor.getString(2));
                event.setFromMinutes(cursor.getInt(3));
                event.setToMinutes(cursor.getInt(4));
                event.setLocation(cursor.getString(5));
                // Adding contact to list
                conList.add(event);
            } while (cursor.moveToNext());
        }

        // return contact list
        return conList;
    }
}

如何解决这个问题?

table 有唯一约束。这意味着只有一行具有给定的 ID 值。如果您尝试更改某行的某些值,请使用 UPDATE 而不是 INSERT。如果您尝试添加此行,则需要为其提供不同的唯一 ID,或者您需要先删除 pre-existing 行。哪一个是正确答案取决于您的应用程序在做什么。

您的代码可能违反了主键对 KEY_ID 字段的唯一性约束。

两种可能的解决方案是:

  1. 确保每个对象的 EventData.getId() returns 唯一值。现在,我没有看到您将任何标识符传递给它的构造函数,也许所有事件都使用相同的 id 值插入。
  2. 如果您不关心自己生成 ID,可以将 AUTOINCREMENT 设置添加到 KEY_ID 列定义中。这样 KEY_ID 字段将自动填充,每一行都有自己的唯一值。到达那里后,不要忘记自己删除将 KEY_ID 添加到 ContentValues

尝试检查该 ID 是否已存在。如果为 true,则不要插入,因为您已经有了具有此 ID 的行。

我原来放的是旧的new unique constraint infant。相反,请确保您当前的唯一列是第一个:

CREATE TABLE TEST (client_id TEXT unique, remote_id INT unique)

我的错误是,我试图填充 ID 列,尽管它已经被定义为 INTEGER PRIMARY KEY AUTOINCREMENT

使id列id整型自增,id值不放入content值中

对于使用 Room Persistence Library 的开发者。您可以使用

@Insert(onConflict = OnConflictStrategy.REPLACE)  // or OnConflictStrategy.IGNORE

根据 Insert Documentation

在 DAO 中

我遇到了同样的问题,问题是我忘记在 DbHelper

中添加 db.execSQL(YOUR_TABLE);

如果您使用 房间 那么您应该使用 @PrimaryKey(autoGenerate = true)

而不是 @PrimaryKey

并使您的 id 变量可选:

@Entity(tableName = "contact_table") data class Contact(@PrimaryKey(autoGenerate = true) @ColumnInfo(name = "id") var id: Long?, @ColumnInfo(name = "name") val name: String, @ColumnInfo(name = "phone") val phone: String)

然后在添加新项目时,将null作为id传递,insert func将return新id,将其添加到您的对象

val contact = Contact(null, name, phone)
contact.id = ContactRoomDatabase.getDatabase().contactDao().insert(contact)

这是数据库中记录id重复的情况。只需清除应用程序存储空间,然后重试。一个好的解决方案是在您的 Dao class.

下方添加
    @Insert (onConflict = OnConflictStrategy.REPLACE)

这个问题的正确解决方法是确保id是唯一的。请看看这个Google Codelabs Room Example

另一种避免这种情况的方法是添加 @PrimaryKey(autoGenerate = true)

对于 Kotlin 模型 类

如果您要像这样向主键分配 默认值

data class MyModel(
 @PrimaryKey(autoGenerate = true) val id: Int = defaultValue
)

确保 LongInt 类型的默认值为 0


来自 autoGenerate 评论:

If the field type is long or int (or its TypeConverter converts it to a long or int), Insert methods treat 0 as not-set while inserting the item.

在我的例子中,我使用 -1 作为默认值并且发生了这个错误。

伙计们,我遇到了同样的问题,我从 android 设置中清除了我的本地数据库并清除了 运行 应用程序,这对我有用。也许你在数据库中做了一点改变而你忘记了。