rawQuery（query，selectionArgs）

Question

我想使用select查詢從表中檢索數據。我發現，rawQuery(query, selectionArgs)方法的SQLiteDatabase類檢索數據。但我不知道如何將query和selectionArgs傳遞給rawQuery方法？ rawQuery的

Answer 1

rawQuery("SELECT id, name FROM people WHERE name = ? AND id = ?", new String[] {"David", "2"}); 

您傳遞數目相等元素的字符串數組，你有「？」

Answer 2

一個例子 - db.rawQuery("select * from table where column = ?",new String[]{"data"});

Answer 3

看下面的代碼它可以幫助你。

String q = "SELECT * FROM customer"; 
Cursor mCursor = mDb.rawQuery(q, null); 

或

String q = "SELECT * FROM customer WHERE _id = " + customerDbId ; 
Cursor mCursor = mDb.rawQuery(q, null); 

Answer 4

也許這可以幫助你

Cursor c = db.rawQuery("query",null); 
int id[] = new int[c.getCount()]; 
int i = 0; 
if (c.getCount() > 0) 
{    
    c.moveToFirst(); 
    do { 
     id[i] = c.getInt(c.getColumnIndex("field_name")); 
     i++; 
    } while (c.moveToNext()); 
    c.close(); 
} 

Answer 5

String mQuery = "SELECT Name,Family From tblName"; 
Cursor mCur = db.rawQuery(mQuery, new String[]{}); 
mCur.moveToFirst(); 
while (!mCur.isAfterLast()) { 
     String name= mCur.getString(mCur.getColumnIndex("Name")); 
     String family= mCur.getString(mCur.getColumnIndex("Family")); 
     mCur.moveToNext(); 
} 

姓名和家庭是你的結果

Answer 6

爲了完整和正確的資源管理：

 ICursor cursor = null; 
     try 
     { 

      cursor = db.RawQuery("SELECT * FROM " + RECORDS_TABLE + " WHERE " + RECORD_ID + "=?", new String[] { id + "" }); 

      if (cursor.Count > 0) 
      { 
       cursor.MoveToFirst(); 
      } 
      return GetRecordFromCursor(cursor); // Copy cursor props to custom obj 
     } 
     finally // IMPORTANT !!! Ensure cursor is not left hanging around ... 
     { 
      if(cursor != null) 
       cursor.Close(); 
     } 

Answer 7

如果您的SQL查詢是這樣的

SELECT name,roll FROM student WHERE name='Amit' AND roll='7' 

然後rawQuery將

String query="SELECT id, name FROM people WHERE name = ? AND roll = ?"; 
String[] selectionArgs = {"Amit","7"} 
db.rawQuery(query, selectionArgs);