WHERE 절을 SELECT 쿼리에 추가하려면 어떻게합니까?

Question

WHERE 절에 정수를 사용하여 행을 선택하는 SQL 쿼리를 작성하려면 어떻게해야합니까?

다음은 쿼리를 사용하려는 코드 조각이지만 아래 코드는 작동하지 않습니다 (결과가 반환되지 않음).

public Cursor forEditPurpose(int pos){ 

    db=this.getReadableDatabase(); 
    Cursor res = db.rawQuery("SELECT name,phone FROM mecontact1 where _id = " + pos + "", null); 

    return res; 

} 

이것은 내가 필요한 모든 작업을 수행 내 전체 데이터베이스 코드 :

public class ContactDatabase extends SQLiteOpenHelper { 
    SQLiteDatabase db; 
    public static final String DATABASE_NAME="totalContact1.db"; 
    public static final String TABLE_NAME="mecontact1"; 
    public static final String NAME="name"; 
    public static final String PHONE="phone"; 
    public static final String UID="_id"; 


    public ContactDatabase(Context context) { 
     super(context, DATABASE_NAME, null, 1); 

    } 

    @Override 
    public void onCreate(SQLiteDatabase db) { 
     try { 
      db.execSQL("create table mecontact1" + 
        "(_id integer primary key , name text, phone text)"); 
     }catch(android.database.SQLException e){ 
       System.out.println("table create nhi ho rha"); 
     } 
    } 

    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
     db.execSQL("DROP TABLE IF EXISTS mecontact1"); 
     onCreate(db); 
    } 

    public void insertContact(String nam,String mob,int autocrement){ 

     db=this.getWritableDatabase(); 
     ContentValues contentValues=new ContentValues(); 

     contentValues.put(NAME,nam); 
     contentValues.put(PHONE,mob); 
     contentValues.put(UID,autocrement); 

     db.insert(TABLE_NAME, null, contentValues); 
     db.close(); 
    } 

    public Cursor showData(){ 

     db=this.getReadableDatabase(); 
     Cursor res = db.rawQuery("SELECT * FROM mecontact1", null); 
     return res; 

    } 

    public Cursor nameData(String dataName){ 

     db=this.getReadableDatabase(); 
     Cursor res = db.rawQuery("SELECT * FROM mecontact1 WHERE name = '"+dataName+"'", null); 
     return res; 

    } 

    public Cursor phoneData(String dataNumber){ 

     db=this.getReadableDatabase(); 
     Cursor res = db.rawQuery("SELECT * FROM mecontact1 WHERE phone = '"+dataNumber+"'", null); 
     return res; 

    } 

    public Cursor phoneName(){ 

     db=this.getReadableDatabase(); 
     Cursor res = db.rawQuery("SELECT * FROM mecontact1 ", null); 
     return res; 

    } 

    public void deleteContact(String d,int pos){ 
     db=this.getWritableDatabase(); 

     db.execSQL("DELETE FROM "+ TABLE_NAME + " WHERE " + UID + " = " + pos +""); 
     db.execSQL("UPDATE " + TABLE_NAME + " set " + UID + " = (" + UID + "-1) where " + UID + " > " + String.valueOf(pos)); 

    } 

    public Cursor forEditPurpose(int pos){ 

     db=this.getReadableDatabase(); 
     Cursor res = db.rawQuery("SELECT name,phone FROM mecontact1 where _id = " + pos + "", null); 

     return res; 

    } 
} 

Answer 1

당신은 시도 할 수 있습니다;

public Cursor forEditPurpose(int pos){ 

    db=this.getReadableDatabase(); 
    //don't forget the ? parameter in the selection 
    Cursor res = db.query(tableName,new String[]{"name","phone"},"_id =?",new String[]{""+pos},null,null,null); 
    return res; 

    } 

Answer 2

나는이 전체 예입니다하지만 코드에서 당신은 아마 cursor.moveToFirst()을 누락 질의 결과의 커서를 반환 할 있으리라 믿고있어;

public Cursor getById(int _id){ 
    SQLiteDatabase db = this.getReadableDatabase(); 

    String selectQuery = "SELECT columns_to_return FROM table_name WHERE column_name = " + _id; 
    Cursor c = db.rawQuery(selectQuery, null); 
    c.moveToFirst(); 

    return c; 
} 

추가 설명이 필요하거나 도움을 요청할 경우 도움을 요청하십시오.