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androids studio sqlite issue with selectionArgs argument

I have the following function in android studio, which is supposed to return a sqlite cursor.
The problem comes in the selectionArgs argument. Whenever I am passing more than one value to it, it returns a cursor with 0 records.
public Cursor getCursor(String strListWhere, String strTable, String strCols) {
String strColsToReturn = mySqliteHandler.getWhereColNamesFromJsonString(strListWhere);
String strArgs = mySqliteHandler.getWhereColArgsFromJsonString(strListWhere);
Log.d(TAG, "qqqq9: " + strArgs);
String strTableName = strTable;
String[] strColumnsToReturn = { strCols };
String strSelectWhere = strColsToReturn ;
String[] strSelectArgs = { strArgs };
Cursor csrResult = sqLiteDatabase.query(true, strTableName, strColumnsToReturn, strSelectWhere, strSelectArgs, null, null, null, null);
Log.d(TAG, "qqqq9: " + csrResult.getCount());
return csrResult;
}
The value in strColsToReturn is animal_class = ? and province_name = ?
The value in strArgs is Bird, KwaZulu-Natal
So I want it to be animal_class = 'Bird' and province_name = 'KwaZulu-natal'
When I only pass one value it works, for example
The value in strColsToReturn is animal_class = ?
The value in strArgs is Bird
Can anyone assist?
EDIT: the following code works:
public Cursor getCursor(String strListWhere, String strTable, String strCols) {
String strColsToReturn = mySqliteHandler.getWhereColNamesFromJsonString(strListWhere);
List<String> arrWhere = new ArrayList<String>();
arrWhere = mySqliteHandler.getWhereArray(strListWhere);
String[] finalValue = new String[ arrWhere.size() ];
arrWhere.toArray( finalValue );
String strTableName = strTable;
String[] strColumnsToReturn = { strCols };
String strSelectWhere = strColsToReturn ;
Cursor csrResult = sqLiteDatabase.query(true, strTableName, strColumnsToReturn, strSelectWhere, finalValue, null, null, null, null);
return csrResult;
}

The value for strColumnsToReturn should be an array with the names of the columns that you want returned, like:
new String[] {column1, column2, column3}
where column1, column2, column3 are strings.
The value for strSelectWhere should be the string:
"animal_class = ? and province_name = ?"
and the value of strSelectArgs should be a string array with the parameters that you pass to each of the ? placeholders of strSelectWhere:
new String {"Bird", "KwaZulu-Natal"}
You can find more here

Pass string variable to db helper and use in query

I have created two string variables, 'questionString' and 'answerSetId' - the first of which I have assigned to a textview - the second of which I would like to pass to my db helper class:
public void showNextRandomQuestion3() {
SQLDatabaseHelper db = new SQLDatabaseHelper(this);
//get the data from the database
List<List<String>> listList = db.getAllAnswersByQuestion1();
//Get the question/text/answer Strings
List<String> questionStrings = listList.get(0); //question Strings
List<String> answerSetIds = listList.get(4);
//Generate random index
Random r = new Random();
int rand = Math.abs((r.nextInt() % questionStrings.size()));
//get answer description for randomly selected question
String questionString = questionStrings.get(rand);
String answerSetId = answerSetIds.get(rand);
questionView.setText(questionString);
}
In my db helper class, I want to use this string variable as pat of my query:
public List<List<String>> getAnswers() {
List<String> array1 = new ArrayList<String>();
List<String> array2 = new ArrayList<String>();
SQLiteDatabase db = this.getReadableDatabase();
String selectQuery = "SELECT * FROM " + TABLE_ANSWERS + "WHERE " + ASID
+ " = " + ??answerSetId??;
Cursor c = db.rawQuery(selectQuery, null);
if (c.moveToFirst()) {
do {
String textdescr = c.getString(c.getColumnIndex(TDESCR));
String answersdescr = c.getString(c.getColumnIndex(ADESCR));
array1.add(textdescr);
array2.add(answersdescr);;
} while (c.moveToNext());
}
List< List<String> > listArray2 = new ArrayList< List<String> >();
listArray2.add(array1);
listArray2.add(array2);
return listArray2;
}
What would be the best way to achieve this?

In order to perform a SELECT, you can use this method
query(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy)
instead of raw query. In your case:
String selection = ASID+"=?";
String selectionArgs[] = new String[]{String.valueOf(answerSetId)};
Cursor c = db.query(TABLE_ANSWERS, null, selection, selectionArgs, null, null, null);
You can also select some specific columns, passing a list of columns name as second parameter (insted of null). Also, you can replace the last three null value in the example for adding the GROUP BY, HAVING and ORDER BY clauses.
For example, in your query you are interested only in the two columns TDESCR and ADESCR. So you could use this query:
String[] columns = new String[]{TDESCR, ADESCR};
String selection = ASID+"=?";
String[] selectionArgs = new String[]{String.valueOf(answerSetId)};
Cursor c = db.query(TABLE_ANSWERS, columns, selection, selectionArgs, null, null, null);
There are a lot of others override methods query. Take a look at the documentation here
However, if you prefer you can perform a raw query in this way:
String queryString = "SELECT * FROM " + TABLE_ANSWERS +
" WHERE "+ASID+"=?";
String[] selectionArgs = new String[]{String.valueOf(answerSetId)};
sqLiteDatabase.rawQuery(queryString, selectionArgs);

how to use where clause in cursor query in sqlite

I want only particular rows that has "E" inside the column "TX_IDT". I used the following code but apps stops. In logcat the error says it is at db.query line.
public Cursor getAllRows( ) {
String where = null;
SQLiteDatabase db = helper.getReadableDatabase();
String[] columns = { VivzHelper.UID, helper.UID,helper.NAME,helper.TX_IDT};
String whereClause = "TX_IDT = ? ";
String[] whereArgs = new String[] { "E" };
Cursor c = db.query( VivzHelper.TABLE_NAME, columns,whereClause,whereArgs, null, null, NAME + " ASC"); // for out btn
if (c != null) {
c.moveToFirst();
}
return c;
}
`

Seems like you want record's containing "E" ,
Try this
Cursor c = db.query(VivzHelper.TABLE_NAME, columns, helper.TX_IDT +" LIKE '%E%' ", null, null, null, null);

querying sqlite using string as where condition

why does when i use a string as a where condition in my database, my program just force close. though it is working fine if i use number as a query condition. please help me, thanks
public ArrayList<Contact> getAvailableList()
{
// TODO Auto-generated method stub
ArrayList<Contact> results = new ArrayList<Contact>();
String[] columns = new String[]{KEY_NAME, KEY_NUMBER, KEY_STATUS};
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_STATUS +"=available" , null, null, null, KEY_NAME);
String sName = "";
String sNum = "";
String status = "";
int iName = c.getColumnIndex(KEY_NAME);
int iNumber = c.getColumnIndex(KEY_NUMBER);
int iStatus = c.getColumnIndex(KEY_STATUS);
Contact contact;
for(c.moveToFirst(); ! c.isAfterLast(); c.moveToNext())
{
contact = new Contact();
sName += c.getString(iName);
sNum += c.getString(iNumber);
status += c.getString(iStatus);
contact.setName(sName);
//contact.setPhoneNumber(sNum);
contact.setPhoneNumber("0".concat(sNum));
contact.setStatus(status);
results.add(contact);
sName = "";
sNum = "";
status = "";
}
return results;
}

You need to wrap strings in SQL with quotes, like this:
// Add these v v
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_STATUS +"='available'",
null, null, null, KEY_NAME);
Or if you want to use dynamic data, you should use the selectionArgs parameter:
String status = "available";
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_STATUS +"=?",
new String[] {status}, null, null, KEY_NAME);
This approach simplifies keeping track of matching quotes in complex Java/SQL Strings, more importantly it protect you from SQL injections.

You forgot ' ' around available
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_STATUS +"='available'" , null, null, null, KEY_NAME);

rawQuery(query, selectionArgs)

I want to use select query for retrieving data from table. I have found, rawQuery(query, selectionArgs) method of SQLiteDatabase class to retrieve data. But I don't know how the query and selectionArgs should be passed to rawQuery method?

rawQuery("SELECT id, name FROM people WHERE name = ? AND id = ?", new String[] {"David", "2"});
You pass a string array with an equal number of elements as you have "?"

Maybe this can help you
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();
}

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

if your SQL query is this
SELECT id,name,roll FROM student WHERE name='Amit' AND roll='7'
then rawQuery will be
String query="SELECT id, name, roll FROM student WHERE name = ? AND roll = ?";
String[] selectionArgs = {"Amit","7"}
db.rawQuery(query, selectionArgs);

see below code it may help you.
String q = "SELECT * FROM customer";
Cursor mCursor = mDb.rawQuery(q, null);
or
String q = "SELECT * FROM customer WHERE _id = " + customerDbId ;
Cursor mCursor = mDb.rawQuery(q, null);

For completeness and correct resource management:
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();
}

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();
}
Name and family are your result