android - sqliteDatabase.delete 实现

Question

如何“翻译”以下 SQL 语句以使用sqliteDatabase.delete(...)-

DELETE FROM EVENTS_TB WHERE event_time < some_time

其中长和event_time是根据用户的选择计算时间。some_timesome_time

Answer 1

您应该使用实例delete()方法。SQLiteDatabase

sq.delete("<tablename>", "event_time < ?", new String {String.valueOf(some_time)});

或更清洁的是，当您声明数据库列之类static final的字段时

static final String KEY_EVENT_TIME = "event_time";
static final String TABLE_NAME = "EVENTS_TB";

sq.delete(TABLE_NAME , KEY_EVENT_TIME + " < ?", new String {String.valueOf(some_time)});

Answer 2

他们来了。它会起作用的

public void deleteAdById(int some_time) {
    final SQLiteDatabase db = getWritableDatabase();
    final String whereClause = event_time  + "<?";
    final String[] whereArgs = new String[] { String.valueOf(some_time) };
    db.delete(EVENTS_TB, whereClause, whereArgs);
    db.close();
}