Develop Reference

Update values of a specific column of a specific row. Android SQLite

I have a recyclerview cardholder that inflates using the values of 'NAME' from the table 'ORDERTABLE'. The cardholder also have an EditText which displays the values of column 'QUANTITY' in my SQLite database.
I also have a button to update the database for every changes in EditText.
I have this table ORDERTABLE
id NAME QUANTITY
1 Order1 1
2 Order2 1
3 Order3 1
4 Order4 1
Being more specific, how can i update the QUANTITY of Order2 on onButtonPressed with the new values of my EditText.
EDIT...
I have tried this code but nothing happened
Button to update values
public void addButtonClick(TextView tv_cardrowName_atc, TextView tv_currentPrice_atc, EditText et_quantity_atc, int position) {
int thisQuantity = Integer.parseInt(et_quantity_atc.getText().toString());
thisQuantity++;
String orderName = tv_cardrowName_atc.getText().toString();
String oldQuantity = et_quantity_atc.getText().toString();
String newQuantity = String.valueOf(thisQuantity);
sqliteCBLCAdapter.selectUpdateItem(orderName, oldQuantity, newQuantity);
et_quantity_atc.setText(String.valueOf(thisQuantity));
}
Update Method
public String selectUpdateItem(String orderName, String oldQuantity, String newQuantity) {
SQLiteDatabase sqLiteDatabase = sqLiteCBLC.getWritableDatabase();
String[] columns = {SQLiteCBLC.COL_ORDNAME, SQLiteCBLC.COL_QUANTITY};
Cursor cursor = sqLiteDatabase.query(SQLiteCBLC.TABLE_NAME, columns, SQLiteCBLC.COL_ORDNAME + " = '" + orderName + "'", null, null, null, null);
StringBuffer stringBuffer = new StringBuffer();
while (cursor.moveToNext()) {
int index1 = cursor.getColumnIndex(SQLiteCBLC.COL_ORDNAME);
int index2 = cursor.getColumnIndex(SQLiteCBLC.COL_QUANTITY);
String order = cursor.getString(index1);
String quantity = cursor.getString(index2);
ContentValues contentValues = new ContentValues();
contentValues.put(SQLiteCBLC.COL_QUANTITY, newQuantity);
String[] whereArgs = {quantity};
sqLiteDatabase.update(SQLiteCBLC.TABLE_NAME, contentValues, SQLiteCBLC.COL_QUANTITY + " =? ", whereArgs);
stringBuffer.append(order);
}
return stringBuffer.toString();
}

The easiest way for you to achieve this would be to use a SQL update query as follows:
From the SQLite Web Site:
The SQLite UPDATE Query is used to modify the existing records in a table. You can use a WHERE clause with UPDATE query to update selected rows, otherwise all the rows would be updated.
The syntax for the update query is as follows:
UPDATE table_name
SET column1 = value1, column2 = value2...., columnN = valueN
WHERE [condition];
So in your case your sql update query would look some thing like this:
UPDATE ORDERTABLE SET QUANTITY = (INSERT VALUE OF YOUR EDIT TEXT) WHERE NAME = 'Order2'
You can then execute your query by using the execSQL() method of your SQLiteDatabase object that you have and passing in the sql query above as the string parameter.

You can try like this below code, In your case you while updating you are updating based on quantity, multiple order will have the same quantity. just check the order name and update it.
public void selectUpdateItem(String orderName, String oldQuantity, String newQuantity) {
if (TextUtils.isEmpty(order)) {
return;
}
ContentValues contentValues = new ContentValues();
final String whereClause = SQLiteCBLC.COL_ORDNAME + " =?";
final String[] whereArgs = {
orderName
};
// if you want to update with respect of quantity too. try this where and whereArgs below
//final String whereClause = SQLiteCBLC.COL_ORDNAME + " =? AND " + SQLiteCBLC.COL_QUANTITY + " =?";
//final String[] whereArgs = {
//orderName, String.valueOf(oldQuantity)
//};
contentValues.put(SQLiteCBLC.COL_QUANTITY, newQuantity);
SQLiteDatabase sqLiteDatabase = sqLiteCBLC.getWritableDatabase();
sqLiteDatabase.update(SQLiteCBLC.TABLE_NAME, contentValues,
whereClause, whereArgs);
}

Android SqlLite check if two values exist in 2 different columns

I am developing an application where the user inputs title and the date. I want to prevent the duplicated titles being inputted on the same day in to database. I am checking if the title exists on the selected date. However my query seems not to work and i don't know why, the application just crashes.Is this query correct? Can someone help?
public boolean checkExist(String title, String date) {
SQLiteDatabase db = this.getWritableDatabase();
Cursor c = db.rawQuery("SELECT * FROM "+TABLE_NAME+" WHERE "+TITLE+"=?" +"AND" + DATE+"=?", new String[] {title,date});
boolean exists = c.moveToFirst();
c.close();
return exists;
}

One issue that you have is that c.moveToFirst will always fail if a match does not exist as you are trying to move to a row in an empty cursor.
The resolution is to not use c.moveToFirst and instead get the count of the rows and then set the return value accordingly.
e.g.
public boolean checkExist(String title, String date) {
SQLiteDatabase db = this.getWritableDatabase();
Cursor c = db.rawQuery("SELECT * FROM "+TABLE_NAME+" WHERE "+TITLE+"=?" +"AND" + DATE+"=?", new String[] {title,date});
boolean exists = c.getCount() > 0;
c.close();
return exists;
}
The second issue is that the query itself is wrong as you do not have spaces either side of the AND keyword. That is instead of
Cursor c = db.rawQuery("SELECT * FROM "+TABLE_NAME+" WHERE "+TITLE+"=?" +"AND" + DATE+"=?", new String[] {title,date});
You should have
Cursor c = db.rawQuery("SELECT * FROM "+TABLE_NAME+" WHERE "+TITLE+"=?" +" AND " + DATE+"=?", new String[] {title,date});
Personally, I setup constants for SQL keywords that include the space and then use these. So I'd have something along the lines of +TITLE+"=?" + SQLAND + DATE+"=?". Where SQLAND would be defined along the lines of String SQLAND=" AND ";
PS look at Cricket_007's answer, the code is neater/better it's easier to read.

Your spacing is off. TITLE+"=?" +"AND" + DATE becomes TITLE=?ANDDATE=?
I would suggest this. See DatabaseUtils.queryNumEntries
public boolean checkExist(String title, String date) {
SQLiteDatabase db = getReadableDatabase();
String[] args = new String[] {title,date};
String filter = String.format("%s=? AND %s=?", TITLE, DATE);
return DatabaseUtils.queryNumEntries(db, TABLE_NAME, filter, args) > 0;
}

you should be using c.getCount() instead of c.moveToFirst()
if the value is greater than 0, then it exists

Update row in SQlite database by row position in android

I have database which contains "date" column and "item" column.
I want that user could update specific row in the database.
I trying to do it with update method in SQLiteDatabase class.
My problem is that i dont know how to make update method find exactly the row i want.
I saw some example that use it with parameters from one word.
like this:
ourDatabase.update(tableName, cvUpdate, rowId + "=" + item , null);
My problem is that i want to update the row that have specific item and date. so the name of the item alone is not enough.
I tried this code below but its didnt work, hope youll can help me.
public void updateEntry(String item, String date) throws SQLException{
String[] columns = new String[]{myItem, myDate};
Cursor c = ourDatabase.query(tableName, columns, null, null, null, null, null);
long position;
ContentValues cvUpdate = new ContentValues();
cvUpdate.put(date, myDate);
cvUpdate.put(item, myExercise);
int itemAll = c.getColumnIndex(myItem);
int dateAll = c.getColumnIndex(myDate);
for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
if (c.getString(itemAll).equals(myItem) && c.getString(dateAll).equals(myDate))
{
position = c.getPosition();
break;
}
}
ourDatabase.update(tableName, cvUpdate, rowId + "=" + position , null);
}

First, the columns String[] is supposed to contain column names, such as "_ID", or whatever are the column names you have used. Given that you compare the content of the column myItem with the object myItem, I assume there is a confusion somewhere here.
Secondly, rowId and position are different things in SQL, especially if you delete rows, as the row id usually is autoincrement, and especially since your query is not explicitely sorted. Replacing c.getPosition() by c.getLong(c.getColumnIndex(ID_COLUMN)) would make more sense.
Thirdly, sql is nice because you can query it. For example, rather than get all items and loop to find the matching date and item, you can :
String whereClause = ITEM_COLUMN + " = ? and " + DATE_COLUMN + " = ?";
String[] whereArgs = new String[] { item, date };
Cursor c = ourDatabase.query(tableName, columns, whereClause, whereArgs, null, null, null);
instead of your for loop.
Forthly, you can even make the query in the update :
String whereClause = ITEM_COLUMN + " = ? and " + DATE_COLUMN + " = ?";
String[] whereArgs = new String[] { item, date };
ourDatabase.update(tableName, cvUpdate, whereClause, whereArgs);
Extra tip: use full caps variable names for contants such as column names, it help with readability.

how to retrieve a specific string data from sqlite database by using 2 string arguments?

this is my code used which i use for making method
String item = item1.getText().toString();
item = item.toLowerCase();
String date = getDate();
edited = new Datahelper(this);
edited.open();
String returnedprice = edited.getprice(item,date);
String returneddetail = edited.getdetail(item,date);
edited.close();
price.setText(returnedprice);
details.setText(returneddetail);
and this is my code of method that i am using for getting that string but here i dont know how to use the 2nd date string so that the string price that return is from a row that contains that item and that date.. please give me the code of how to do it..
public String getprice(String item ,String date) {
// TODO Auto-generated method stub
String[] columns = new String[]{KEY_ROWID,
KEY_CATEGORY,KEY_DATE,KEY_PRICE,KEY_DETAILS};
Cursor v =ourDatabase.query(DATABASE_TABLE, columns, KEY_CATEGORY + " ='" + item
+"'",null,null, null, null);
if(v!=null){
String price = v.getString(3);
return price;
}
return null;
}
public String getdetail(String item,String date) {
// TODO Auto-generated method stub
String[] columns = new String[]{KEY_ROWID,
KEY_CATEGORY,KEY_DATE,KEY_PRICE,KEY_DETAILS};
Cursor v =ourDatabase.query(DATABASE_TABLE, columns, KEY_CATEGORY + " ='" + item +
"'",null,null, null, null);
if(v!=null){
String detail = v.getString(4);
return detail;
}
return null;
}

So probably you want to use two arguments in select query so:
You can use two methods:
rawQuery()
query()
I will give you basic example for both cases.
First:
String query = "select * from Table where someColumn = ? and someDateColumn = ?";
Cursor c = db.rawQuery(query, new String[] {textValue, dateValue});
Explanation:
So i recommend to you use ? that is called placeholder.
Each placeholder in select statement will be replaced(in same order so first placeholder will be replaced by first value in array etc.) by values from selectionArgs - it's String array declared above.
Second:
rawQuery() method was easier to understand so i started with its. Query() method is more complex and has a little bit more arguments. So
columns: represents array of columns will be selected.
selection: is in other words where clause so if your selection is
KEY_COL + " = ?" it means "where " + KEY_COL + " = ?"
selectionArgs: each placeholder will be replaced with value from this
array.
groupBy: it's multi-row (grouping) function. more
about
having: this clause is always used with group by clause here is
explanation
orderBy: is clause used for sorting rows based on one or multiple
columns
Also method has more arguments but now you don't need to care about them. If you will, Google will be your friend.
So let's back to explanation and example:
String[] columns = {KEY_COL1, KEY_COL2};
String whereClause = KEY_CATEGORY " = ? and " + KEY_DATE + " = ?";
String[] whereArgs = {"data1", "data2"};
Cursor c = db.query("Table", columns, whereClause, whereArgs, null, null, null);
So whereClause contains two arguments with placeholder for each. So first placeholder will be replaced with "data1" and second with "data2".
When query is performed, query will look like:
SELECT col1, col2 FROM Table WHERE category = 'data1' AND date = 'data2'
Note: I recommend to you have look at Android SQLite Database and ContentProvider - Tutorial.
Also i recommend to you an usage of placeholders which provide safer and much more readable and clear solutions.

You should read any SQL tutorial to find out what a WHERE clause it and how to write it.
In Android, the selection parameter is the expression in the WHERE clause.
Your query could be written like this:
c = db.query(DATABASE_TABLE, columns,
KEY_CATEGORY + " = ? AND " + KEY_DATE + " = ?",
new String[] { item, date },
null, null, null);

How to pass multiple values to query dynamically in android?

In my project I have to select multiple values and pass it to a query. i.e page1 contains checkboxes. I am storing the selected checkbox id's into an array.
I am shuffling that array and getting the values randomly. Now I need to pass these random values to a query. Using IN operator in database I can pass the values
statically but how can I pass the values dynamcially to the query.
For ex:(Passing values statically)
SELECT * FROM Persons WHERE person_id IN ('21','22')
In the above query the id's 21 and 22 are know previously and so we are passing statically but I want to send the values to query dynamically.
Page1:
public static ArrayList<String> chksublist = new ArrayList<String>();
Page2:
Collections.shuffle(chksublist );
SELECT * FROM Persons WHERE person_id IN ('21','22')
In the above line I want to send the random values which are in chksublist array.

String query = "SELECT * FROM Persons WHERE person_id IN (" + TextUtils.join(",", chksublist) + ")";
But shuffling the chksublist before sending it to your SQL query has no impact on the result set you get from SQL. It will not randomly permute your results. Remove Collections.shuffle(chksublist); and use
String query = "SELECT * FROM Persons WHERE person_id IN (" + TextUtils.join(",", chksublist) + ") ORDER BY RANDOM()";

see how values are dynamicaly passed
// Getting single contact
public Contact getContact(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_CONTACTS, new String[] { KEY_ID,
KEY_NAME, KEY_PH_NO }, KEY_ID + "=?",
new String[] { String.valueOf(id) }, null, null, null, null);
// here new String[] { String.valueOf(id) } value is added dynamicaly which is passed to the function
if (cursor != null)
cursor.moveToFirst();
Contact contact = new Contact(Integer.parseInt(cursor.getString(0)),
cursor.getString(1), cursor.getString(2));
// return contact
return contact;
}

You can generate your query like this
int values[]; //it contains your generated values like 21,22....
String query="SELECT * FROM Persons WHERE person_id IN (";
for(int i=0;i<values.length;i++){
query=query+"'"+values[i]+"'";
if(i<values.length-1){
query=query+","; //No , after last values
}
}
query+=")";
finally pass this query.

Try it
cursor = database.query(tablename,
new String[] {"TopName"}, "id IN(?,?)", new String[]{"2","3"}, null, null, null);
using raw query
String query = "SELECT * FROM Persons WHERE person_id IN ("+parameter1+","+parameter2+")";
db.rawQuery(query);