Question

当插入sqlite数据库时，Sqlite中的

id不会生成唯一的id。有大学名单，大学名单和学校名单，我必须加入书签。当我为学校的第一项添加书签时，学院和大学的项目都被加入书签。如何解决？

DatabaseHelper类

<script type="text/javascript">
         var check = 0;
         var ok;
</script>
<div ng-repeat="house in houses">
  <div ng-repeat="img in house_imgs">
    <section ng-if="house.id == img.house_id">
       <script type="text/javascript">
           check = 1;
           ok = img.house_img;
       </script>
    </section>
  </div>

  <div ng-if="check == 1">
      <img src="{{asset('house_img/')}}/@{{ok}}" >
  </div>
</div>

BookmarkAdapter类

package com.javacodegeeks.enterprise.rest.javaneturlclient;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class JavaNetURLRESTFulClient {

    private static final String targetURL = "http://localhost:8080/w/JSONService";

    public static void main(String[] args) {

        try {

            URL targetUrl = new URL(targetURL);

            HttpURLConnection httpConnection = (HttpURLConnection) targetUrl.openConnection();
            httpConnection.setDoOutput(true);
            httpConnection.setRequestMethod("POST");
            httpConnection.setRequestProperty("Content-Type", "application/json");

            String input = "{\"id\":1,\"firstName\":\"Liam\",\"age\":22,\"lastName\":\"Marco\"}";

            OutputStream outputStream = httpConnection.getOutputStream();
            outputStream.write(input.getBytes());
            outputStream.flush();

            if (httpConnection.getResponseCode() != 200) {
                throw new RuntimeException("Failed : HTTP error code : "
                    + httpConnection.getResponseCode());
            }

            BufferedReader responseBuffer = new BufferedReader(new InputStreamReader(
                    (httpConnection.getInputStream())));

            String output;
            System.out.println("Output from Server:\n");
            while ((output = responseBuffer.readLine()) != null) {
                System.out.println(output);
            }

            httpConnection.disconnect();

          } catch (MalformedURLException e) {

            e.printStackTrace();

          } catch (IOException e) {

            e.printStackTrace();

         }

        }    
    }

DatabaseupdatedListener

public class DatabaseHelper extends SQLiteOpenHelper {
    public DatabaseUpdatedListener databaseUpdatedListener;
    static final String DATABASE_NAME = "BookmarkDatabase";
    private static final int DATABASE_VERSION = 1;
    private static final String TABLE_NAME_BOOKMARK = "bookmark";
    //    Contact table columns name
    private static final String ID = "Id";
    private static final String NAME = "Name";
    private static final String ADDRESS = "Address";
    private static final String LOGO = "Logo";
    private static final String COUNTRY = "country";
    private static final String PHONE = "phone";
    private static final String EMAIL = "email";
    private static final String WEBSITE = "website";
    private static final String INSTITUTION_TYPE = "institution_type";
    private static final String ESTABLISHED_DATE = "establishment_date";
    private static final String ADMISSION_OPEN_FROM = "admission_open_from";
    private static final String ADMISSION_OPEN_TO = "admission_open_to";
    private static final String LATITUDE = "latitude";
    private static final String LONGITUDE = "longitude";

    String createTableBookmark = "Create table if not exists `Bookmark` (" + "`name`    TEXT," + "`location`    TEXT," + "`logo`    TEXT);";
    String CREATE_SCHOOL_BOOKMARK_TABLE = "CREATE TABLE " + TABLE_NAME_BOOKMARK + "("
            + ID + " INTEGER PRIMARY KEY AUTOINCREMENT "
            + NAME + " TEXT, "
            + LOGO + " TEXT, "
            + ADDRESS + " TEXT, "
            + COUNTRY + " TEXT, "
            + PHONE + " TEXT, "
            + EMAIL + " TEXT, "
            + WEBSITE + " TEXT, "
            + INSTITUTION_TYPE + " TEXT, "
            + ESTABLISHED_DATE + " TEXT, "
            + ADMISSION_OPEN_FROM + " TEXT, "
            + ADMISSION_OPEN_TO + " TEXT, "
            + LATITUDE + " TEXT, "
            + LONGITUDE + " TEXT " + ")";

    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    public void insertBookmarkData(Bookmarkitem bookmarkitem) {
        SQLiteDatabase db = getWritableDatabase();
        ContentValues content = new ContentValues();
        content.put("name", bookmarkitem.name);
        content.put("location", bookmarkitem.address);
        content.put("logo", bookmarkitem.logo);

        db.insert("Bookmark", null, content);
    }

    public ArrayList<Bookmarkitem> getBookmarkist() {
        String sql = "select * from Bookmark ";
        ArrayList<Bookmarkitem> bookmarklist = new ArrayList<Bookmarkitem>();

        Cursor c = getWritableDatabase().rawQuery(sql, null);
        while (c.moveToNext()) {
            Bookmarkitem info = new Bookmarkitem();
            info.name = c.getString(c.getColumnIndex("name"));
            info.address = c.getString(c.getColumnIndex("location"));
            info.logo = c.getString(c.getColumnIndex("logo"));
            bookmarklist.add(info);
        }
        c.close();
        return bookmarklist;
    }

    public Bookmarkitem getBookmarkData(String bookmarkName) {
        String sql = "select * from Bookmark  where id='" + bookmarkName + "'";

        Cursor c = getWritableDatabase().rawQuery(sql, null);
        while (c.moveToNext()) {
            Bookmarkitem info = new Bookmarkitem();
            info.name = c.getString(c.getColumnIndex("name"));
            info.address = c.getString(c.getColumnIndex("location"));
            info.logo = c.getString(c.getColumnIndex("logo"));
        }
        c.close();
        Bookmarkitem info = null;
        return info;
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {
        // TODO Auto-generated method stub

        sqLiteDatabase.execSQL(CREATE_SCHOOL_BOOKMARK_TABLE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int arg1, int arg2) {
        // TODO Auto-generated method stub


        sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME_BOOKMARK);
        onCreate(sqLiteDatabase);
    }

    public void addSchoolBookmark(Bookmarkitem bookmarkitem, MenuItem menuItem) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(ID, bookmarkitem.getBookmarkID());


        values.put(NAME, bookmarkitem.getName());
        values.put(LOGO, bookmarkitem.getLogo());
        values.put(ADDRESS, bookmarkitem.getAddress());

        values.put(COUNTRY, bookmarkitem.getCountry());
        values.put(PHONE, bookmarkitem.getPhone());
        values.put(EMAIL, bookmarkitem.getEmail());
        values.put(WEBSITE, bookmarkitem.getWebsite());
        values.put(INSTITUTION_TYPE, bookmarkitem.getInstitution_type());
        values.put(ESTABLISHED_DATE, bookmarkitem.getEstablishment_date());
        values.put(ADMISSION_OPEN_FROM, bookmarkitem.getAdmission_open_from());
        values.put(ADMISSION_OPEN_TO, bookmarkitem.getAdmission_open_to());
        values.put(LATITUDE, bookmarkitem.getLatitude());
        values.put(LONGITUDE, bookmarkitem.getLongitude());


        //inserting row
        if (db.insert(TABLE_NAME_BOOKMARK, null, values) != -1) {
            //
            databaseUpdatedListener.setDatabaseSuccess(bookmarkitem.getName(), menuItem);


        }

     /*   else {
            databaseUpdatedListener.setDatabaseError("Failed to Delete");
        }   */

//        db.beginTransaction();


        db.close();
    }

    public List<Bookmarkitem> getAllSchoolBookmark() {
        SQLiteDatabase db = this.getWritableDatabase();
        String selectQuery = "SELECT * FROM " + TABLE_NAME_BOOKMARK;
        List<Bookmarkitem> bookmarkitems = new ArrayList<>();
        Cursor cursor = db.rawQuery(selectQuery, null);

        if (cursor.moveToFirst()) {
            do {
                Bookmarkitem bookmarkitem = new Bookmarkitem();
                bookmarkitem.setBookmarkID(Integer.parseInt(cursor.getString(0)));
                bookmarkitem.setName(cursor.getString(1));
                bookmarkitem.setLogo(cursor.getString(2));
                bookmarkitem.setAddress(cursor.getString(3));

                bookmarkitem.setCountry(cursor.getString(4));
                bookmarkitem.setPhone(cursor.getString(5));
                bookmarkitem.setEmail(cursor.getString(6));
                bookmarkitem.setWebsite(cursor.getString(7));
                bookmarkitem.setInstitution_type(cursor.getString(8));
                bookmarkitem.setEstablishment_date(cursor.getString(9));
                bookmarkitem.setAdmission_open_from(cursor.getString(10));
                bookmarkitem.setAdmission_open_to(cursor.getString(11));
                bookmarkitem.setLatitude(cursor.getString(12));
                bookmarkitem.setLongitude(cursor.getString(13));

                bookmarkitems.add(bookmarkitem);
            } while (cursor.moveToNext());
        }
        return bookmarkitems;
    }

    public boolean removeBookmarkItem(String id) {
        SQLiteDatabase db = this.getWritableDatabase();
        return db.delete(TABLE_NAME_BOOKMARK, ID + "=" + id, null) > 0;
    }

    public Bookmarkitem getBoomarkDetailByID(String id) {
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = null;
        String empName = "";
        try {
            Bookmarkitem bookmarkitem = new Bookmarkitem();
            cursor = db.rawQuery("SELECT * FROM " + TABLE_NAME_BOOKMARK + " WHERE " + ID + "=?", new String[]{id + ""});
            if (cursor.getCount() > 0) {

                cursor.moveToFirst();
                bookmarkitem.setBookmarkID(Integer.parseInt(cursor.getString(0)));
                bookmarkitem.setName(cursor.getString(1));
                bookmarkitem.setLogo(cursor.getString(2));
                bookmarkitem.setAddress(cursor.getString(3));

                bookmarkitem.setCountry(cursor.getString(4));
                bookmarkitem.setPhone(cursor.getString(5));
                bookmarkitem.setEmail(cursor.getString(6));
                bookmarkitem.setWebsite(cursor.getString(7));
                bookmarkitem.setInstitution_type(cursor.getString(8));
                bookmarkitem.setEstablishment_date(cursor.getString(9));
                bookmarkitem.setAdmission_open_from(cursor.getString(10));
                bookmarkitem.setAdmission_open_to(cursor.getString(11));
                bookmarkitem.setLatitude(cursor.getString(12));
                bookmarkitem.setLongitude(cursor.getString(13));
            }

            return bookmarkitem;
        } finally {

            cursor.close();
        }
    }
}

在数据库中插入时没有生成唯一ID。如何解决？

Answer 1

问题

不同的字段名称。

 private static final String ID = "Id";
 String sql = "select * from Bookmark  where id='" + bookmarkName + "'"; // why id ? must be ID

纠正 getBookmarkData 方法

演示示例。

      private static final String USER_ID= "user_id";

      String sql = "select * from Bookmark  where user_id='" + bookmarkName + "'";

     cursor = db.rawQuery("SELECT * FROM " + TABLE_NAME_BOOKMARK + " WHERE " + USER_ID+ "=?", new String[]{id + ""});

然后卸载旧应用并重新运行。

Answer 2

您无需明确添加ID列。请尝试以下。

首先为列名创建合约类

public static class ColumnNameEntry implements BaseColumns {
private static final String NAME = "Name";
private static final String ADDRESS = "Address";
private static final String LOGO = "Logo";
private static final String COUNTRY = "country";
private static final String PHONE = "phone";
private static final String EMAIL = "email";
private static final String WEBSITE = "website";
private static final String INSTITUTION_TYPE = "institution_type";
private static final String ESTABLISHED_DATE = "establishment_date";
private static final String ADMISSION_OPEN_FROM = "admission_open_from";
private static final String ADMISSION_OPEN_TO = "admission_open_to";
private static final String LATITUDE = "latitude";
private static final String LONGITUDE = "longitude";
}

实施BaseColumns类会自动提供列_id，这将自动递增

现在创建表格如下

String CREATE_SCHOOL_BOOKMARK_TABLE = "CREATE TABLE " + TABLE_NAME_BOOKMARK + "("
        + ColumnNameEntry._ID + " INTEGER PRIMARY KEY "....

参考this教程

在Sqlite数据库中的Id碰撞？

2 个答案:

问题