android sqlite 建增删改查

1、继承SqliteOpenHelper类

public class MyOpenHelper extends SQLiteOpenHelper {
    public static final String DB_NAME="student.db";

    public MyOpenHelper(Context context) {
        super(context, DB_NAME, null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
       db.execSQL("create table person(_id integer primary key autoincrement,name char(10),money integer(10))");
    }

    @Override
    public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
    }

}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

2、获取数据库实例

    MyOpenHelper oh=new MyOpenHelper(getContext());
    SQLiteDatabase db=oh.getWritableDatabase();
1
2

3、数据库增删查改操作 
（1）插入

    public void insertDatebase(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db=oh.getWritableDatabase();
        db.execSQL("insert into person(name,money) values('ppa',7000);");
        db.close();
    }
1
2
3
4
5
6

API插入
    ContentValues cv=new ContentValues();
        cv.put("name", "ppa");
        cv.put("money", 16000);
        long id = db.insert("person", null, cv);
1
2
3
4
5

（2）更新

public void updateDatabase(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db = oh.getWritableDatabase();
        db.execSQL("update person set money=? where name=?",new Object[]{13000,"ppa"});
    }
1
2
3
4
5

API更新
ContentValues cv=new ContentValues();
        cv.put("money", 16005);
        int num = db.update("person", cv, "name=?", new String[]{"ppa"});
1
2
3
4

（3）删除

    public void deleteDatabase(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db=oh.getWritableDatabase();
        db.execSQL("delete from person where name ='李四'");
        db.close();
    }
1
2
3
4
5
6

API删除
int num = db.delete("person", "name=?", new String[]{"李四"});
1
2

(4)查询

public void select(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db = oh.getWritableDatabase();
//      Cursor cursor = db.rawQuery("select name,money from person", null);
        Cursor cursor = db.rawQuery("select * from person where name=?", new String[]{"潘平安"} );
        while (cursor.moveToNext()) {
            String name = cursor.getString(cursor.getColumnIndex("name"));
            String money = cursor.getString(2);
            System.out.println(name+";"+money);
        }
    }
1
2
3
4
5
6
7
8
9
10
11

API查询
    Cursor cursor = db.query("person", new String[]{"name","money"}, "name=?", new String[]{"ppa"}, null, null, null);
1
2

1、继承SqliteOpenHelper类

public class MyOpenHelper extends SQLiteOpenHelper {
    public static final String DB_NAME="student.db";

    public MyOpenHelper(Context context) {
        super(context, DB_NAME, null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
       db.execSQL("create table person(_id integer primary key autoincrement,name char(10),money integer(10))");
    }

    @Override
    public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
    }

}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
2、获取数据库实例

    MyOpenHelper oh=new MyOpenHelper(getContext());
    SQLiteDatabase db=oh.getWritableDatabase();
1
2
3、数据库增删查改操作 
（1）插入

    public void insertDatebase(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db=oh.getWritableDatabase();
        db.execSQL("insert into person(name,money) values('ppa',7000);");
        db.close();
    }
1
2
3
4
5
6
API插入
    ContentValues cv=new ContentValues();
        cv.put("name", "ppa");
        cv.put("money", 16000);
        long id = db.insert("person", null, cv);
1
2
3
4
5
（2）更新

public void updateDatabase(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db = oh.getWritableDatabase();
        db.execSQL("update person set money=? where name=?",new Object[]{13000,"ppa"});
    }
1
2
3
4
5
API更新
ContentValues cv=new ContentValues();
        cv.put("money", 16005);
        int num = db.update("person", cv, "name=?", new String[]{"ppa"});
1
2
3
4
（3）删除

    public void deleteDatabase(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db=oh.getWritableDatabase();
        db.execSQL("delete from person where name ='李四'");
        db.close();
    }
1
2
3
4
5
6
API删除
int num = db.delete("person", "name=?", new String[]{"李四"});
1
2
(4)查询

public void select(){
        MyOpenHelper oh=new MyOpenHelper(getContext());
        SQLiteDatabase db = oh.getWritableDatabase();
//      Cursor cursor = db.rawQuery("select name,money from person", null);
        Cursor cursor = db.rawQuery("select * from person where name=?", new String[]{"潘平安"} );
        while (cursor.moveToNext()) {
            String name = cursor.getString(cursor.getColumnIndex("name"));
            String money = cursor.getString(2);
            System.out.println(name+";"+money);
        }
    }
1
2
3
4
5
6
7
8
9
10
11

API查询
    Cursor cursor = db.query("person", new String[]{"name","money"}, "name=?", new String[]{"ppa"}, null, null, null);
1
2