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SQLite in Android How to update a specific row

I've been trying to update a specific row for a while now, and it seems that there are two ways to do this. From what I've read and tried, you can just use the:

execSQL(String sql) method

or the:

update(String table, ContentValues values, String whereClause, String[] whereArgs) method.

(Let me know if this is incorrect as I am new to android and very new to SQL.)

So let me get to my actual code.

myDB.update(TableName, "(Field1, Field2, Field3)" + " VALUES ('Bob', 19, 'Male')", "where _id = 1", null);

I am trying to accomplish this:

Update Field1, Field2, and Field3 where the primary key (_id) is equal to 1.

Eclipse gives me a red line right underneath the word "update" and gives me this explanation:

The method update(String, ContentValues, String, String[]) in the type SQLiteDatabase is not applicable for the arguments (String, String, String, null)

I'm guessing I'm not assigning the ContentValues correctly. Can anyone point me in the right direction?

First make a ContentValues object :

ContentValues cv = new ContentValues();
cv.put("Field1","Bob"); //These Fields should be your String values of actual column names
cv.put("Field2","19");
cv.put("Field2","Male");

Then use the update method, it should work now:

myDB.update(TableName, cv, "_id = ?", new String[]{id});

Simple way:

String strSQL = "UPDATE myTable SET Column1 = someValue WHERE columnId = "+ someValue;

myDataBase.execSQL(strSQL);

At first create a ContentValues object :

ContentValues cv = new ContentValues();
cv.put("Field1","Bob");
cv.put("Field2","19");

Then use the update method. Note, the third argument is the where clause. The "?" is a placeholder. It will be replaced with the fourth argument (id)

myDB.update(MY_TABLE_NAME, cv, "_id = ?", new String[]{id});

This is the cleanest solution to update a specific row.

  1. I personally prefere .update for its convenience. But execsql will work same.
  2. You are right with your guess that the problem is your content values. You should create a ContentValue Object and put the values for your database row there.

This code should fix your example:

 ContentValues data=new ContentValues();
 data.put("Field1","bob");
 data.put("Field2",19);
 data.put("Field3","male");
 DB.update(Tablename, data, "_id=" + id, null);

你可以试试这个...

db.execSQL("UPDATE DB_TABLE SET YOUR_COLUMN='newValue' WHERE id=6 ");

hope this'll help you:

public boolean updatedetails(long rowId, String address)
  {
     SQLiteDatabase mDb= this.getWritableDatabase();
   ContentValues args = new ContentValues();
   args.put(KEY_ROWID, rowId);          
   args.put(KEY_ADDRESS, address);
  return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null)>0;   
 }

You try this one update method in SQLite

int id;
ContentValues con = new ContentValues();
con.put(TITLE, title);
con.put(AREA, area);
con.put(DESCR, desc);
con.put(TAG, tag);
myDataBase.update(TABLE, con, KEY_ID + "=" + id,null);

use this code in your DB `

public boolean updatedetails(long rowId,String name, String address)
      {
       ContentValues args = new ContentValues();
       args.put(KEY_ROWID, rowId);          
       args.put(KEY_NAME, name);
       args.put(KEY_ADDRESS, address);
       int i =  mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null);
    return i > 0;
     }

for updating in your sample.java use this code

  //DB.open();

        try{
              //capture the data from UI
              String name = ((EditText)findViewById(R.id.name)).getText().toString().trim();
              String address =(EditText)findViewById(R.id.address)).getText().toString().trim();

              //open Db
              pdb.open();

              //Save into DBS
              pdb.updatedetails(RowId, name, address);
              Toast.makeText(this, "Modified Successfully", Toast.LENGTH_SHORT).show();
              pdb.close();
              startActivity(new Intent(this, sample.class));
              finish();
        }catch (Exception e) {
            Log.e(TAG_AVV, "errorrrrr !!");
            e.printStackTrace();
        }
    pdb.close();

Can try like this:

ContentValues values=new ContentValues();
values.put("name","aaa");
values.put("publisher","ppp");
values.put("price","111");

int id=sqdb.update("table_name",values,"bookid='5' and booktype='comic'",null);

For updates, need to call setTransactionSuccessfull for changes to get committed like so:

db.beginTransaction();
try {
    db.update(...) 
    db.setTransactionSuccessfull(); // changes get rolled back if this not called
} finally {
   db.endTransaction(); // commit or rollback
}

//Here is some simple sample code for update

//First declare this

private DatabaseAppHelper dbhelper;
private SQLiteDatabase db;

//initialize the following

dbhelper=new DatabaseAppHelper(this);
        db=dbhelper.getWritableDatabase();

//updation code

 ContentValues values= new ContentValues();
                values.put(DatabaseAppHelper.KEY_PEDNAME, ped_name);
                values.put(DatabaseAppHelper.KEY_PEDPHONE, ped_phone);
                values.put(DatabaseAppHelper.KEY_PEDLOCATION, ped_location);
                values.put(DatabaseAppHelper.KEY_PEDEMAIL, ped_emailid);
                db.update(DatabaseAppHelper.TABLE_NAME, values,  DatabaseAppHelper.KEY_ID + "=" + ?, null);

//put ur id instead of the 'question mark' is a function in my shared preference.

 public void updateRecord(ContactModel contact) {
    database = this.getReadableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(COLUMN_FIRST_NAME, contact.getFirstName());
    contentValues.put(COLUMN_LAST_NAME, contact.getLastName());
    contentValues.put(COLUMN_NUMBER,contact.getNumber());
    contentValues.put(COLUMN_BALANCE,contact.getBalance());
    database.update(TABLE_NAME, contentValues, COLUMN_ID + " = ?", new String[]{contact.getID()});
    database.close();
}

如果您的 sqlite 行具有唯一的 id 或其他等效项,则可以使用 where 子句,如下所示

update .... where id = {here is your unique row id}

just try this way

  String strFilter = "_id=" + Id;
  ContentValues args = new ContentValues();
  args.put(KEY_TITLE, title);
  myDB.update("titles", args, strFilter, null);**

Method for updation in SQLite:

public void updateMethod(String name, String updatename){
    String query="update students set email = ? where name = ?";
    String[] selections={updatename, name};
    Cursor cursor=db.rawQuery(query, selections);
}

I will demonstrate with a complete example

Create your database this way

    import android.content.Context
    import android.database.sqlite.SQLiteDatabase
    import android.database.sqlite.SQLiteOpenHelper

    class DBHelper(context: Context) : SQLiteOpenHelper(context, DATABASE_NAME, null, DATABASE_VERSION) {
        override fun onCreate(db: SQLiteDatabase) {
            val createProductsTable = ("CREATE TABLE " + Business.TABLE + "("
                    + Business.idKey + " INTEGER PRIMARY KEY AUTOINCREMENT ,"
                    + Business.KEY_a + " TEXT, "
                    + Business.KEY_b + " TEXT, "
                    + Business.KEY_c + " TEXT, "
                    + Business.KEY_d + " TEXT, "
                    + Business.KEY_e + " TEXT )")
            db.execSQL(createProductsTable)
        }
        override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
            // Drop older table if existed, all data will be gone!!!
            db.execSQL("DROP TABLE IF EXISTS " + Business.TABLE)
            // Create tables again
            onCreate(db)

        }
        companion object {
            //version number to upgrade database version
            //each time if you Add, Edit table, you need to change the
            //version number.
            private val DATABASE_VERSION = 1

            // Database Name
            private val DATABASE_NAME = "business.db"
        }
    }

Then create a class to facilitate CRUD -> Create|Read|Update|Delete

class Business {
    var a: String? = null
    var b: String? = null
    var c: String? = null
    var d: String? = null
    var e: String? = null

    companion object {
        // Labels table name
        const val TABLE = "Business"
        // Labels Table Columns names
        const val rowIdKey = "_id"
        const val idKey = "id"
        const val KEY_a = "a"
        const val KEY_b = "b"
        const val KEY_c = "c"
        const val KEY_d = "d"
        const val KEY_e = "e"
    }
}

Now comes the magic

import android.content.ContentValues
import android.content.Context

    class SQLiteDatabaseCrud(context: Context) {
        private val dbHelper: DBHelper = DBHelper(context)

        fun updateCart(id: Int, mBusiness: Business) {
            val db = dbHelper.writableDatabase
            val valueToChange = mBusiness.e
            val values = ContentValues().apply {
                put(Business.KEY_e, valueToChange)
            }
            db.update(Business.TABLE, values, "id=$id", null)
            db.close() // Closing database connection
        }
    }

you must create your ProductsAdapter which must return a CursorAdapter

So in an activity just call the function like this

internal var cursor: Cursor? = null
internal lateinit var mProductsAdapter: ProductsAdapter

 mSQLiteDatabaseCrud = SQLiteDatabaseCrud(this)
    try {
        val mBusiness = Business()
        mProductsAdapter = ProductsAdapter(this, c = todoCursor, flags = 0)
        lstProducts.adapter = mProductsAdapter


        lstProducts.onItemClickListener = OnItemClickListener { parent, view, position, arg3 ->
                val cur = mProductsAdapter.getItem(position) as Cursor
                cur.moveToPosition(position)
                val id = cur.getInt(cur.getColumnIndexOrThrow(Business.idKey))

                mBusiness.e = "this will replace the 0 in a specific position"
                mSQLiteDatabaseCrud?.updateCart(id ,mBusiness)

            }

        cursor = dataBaseMCRUD!!.productsList
        mProductsAdapter.swapCursor(cursor)
    } catch (e: Exception) {
        Log.d("ExceptionAdapter :",""+e)
    }

在此处输入图片说明

SQLiteDatabase myDB = this.getWritableDatabase();

ContentValues cv = new ContentValues();
cv.put(key1,value1);    
cv.put(key2,value2); /*All values are your updated values, here you are 
                       putting these values in a ContentValues object */
..................
..................

int val=myDB.update(TableName, cv, key_name +"=?", new String[]{value});

if(val>0)
 //Successfully Updated
else
 //Updation failed

Here I have completed this kind of code for update the row of a database, this is the code of Database handler class

public Boolean updateData(String id,String name,String age,String gender){
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(ID,id);
    contentValues.put(NAME,name);
    contentValues.put(AGE,age);
    contentValues.put(GENDER,gender);

    sqLiteDatabase.update(TABLE_NAME,contentValues,ID+"= ?",new String[]{id});
    return true;           //Boolean value return korbe
}

I've been trying to update a specific row for a while now, and it seems that there are two ways to do this. From what I've read and tried, you can just use the:

execSQL(String sql) method

or the:

update(String table, ContentValues values, String whereClause, String[] whereArgs) method.

(Let me know if this is incorrect as I am new to android and very new to SQL.)

So let me get to my actual code.

myDB.update(TableName, "(Field1, Field2, Field3)" + " VALUES ('Bob', 19, 'Male')", "where _id = 1", null);

I am trying to accomplish this:

Update Field1, Field2, and Field3 where the primary key (_id) is equal to 1.

Eclipse gives me a red line right underneath the word "update" and gives me this explanation:

The method update(String, ContentValues, String, String[]) in the type SQLiteDatabase is not applicable for the arguments (String, String, String, null)

I'm guessing I'm not assigning the ContentValues correctly. Can anyone point me in the right direction?

public long fillDataTempo(String table){
    String[] table = new String[1];
    tabela[0] = table; 
    ContentValues args = new ContentValues();
    args.put(DBOpenHelper.DATA_HORA, new Date().toString());
    args.put(DBOpenHelper.NOME_TABELA, nome_tabela);
    return db.update(DATABASE_TABLE, args, STRING + " LIKE ?" ,tabela);
}

just give rowId and type of data that is going to be update in ContentValues.

public void updateStatus(String id , int status){

SQLiteDatabase db = this.getWritableDatabase();

ContentValues data = new ContentValues();

data.put("status", status);

db.update(TableName, data, "columnName" + " = "+id , null);

}

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