android get count total rows? - android

I will appreciate if someone help me with this code below:
i'm trying to get total rows in my table: i'm calling from the button but it always crash...
public int countjournals() {
Cursor dataCount = CountryDB.rawQuery("select count(*) from" + TABLE_NAME, null);
dataCount.moveToFirst();
int jcount = dataCount.getInt(0);
dataCount.close();
Toast.makeText(getApplicationContext(),
"Total:", Toast.LENGTH_LONG).show();
return jcount;
}
I have created it method in CountyDB like this:
public static Cursor rawQuery(String string, Object object) {
// TODO Auto-generated method stub
return null;
}
thanks in advance

First you need to either implement your rawQuery() or remove it. What you want is SQLiteDatabase's rawQuery().
Also, you need space between from and table name here:
"select count(*) from" + TABLE_NAME
change to:
"select count(*) from " + TABLE_NAME

Ideally it should work if not....
rawQuery method is returning null every time it seems once check with that
public static Cursor rawQuery(String string, Object object) {
// TODO Auto-generated method stub
return null;
}

private int getCount(){
int count = 0;
String query = "SELECT * FROM "+"Table_Name";
Cursor cursor = CountryDB.rawQuery(query, null);
while(!cursor.isAfterLast()){
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
int x = cursor.getInt(0);
Log.e("", "x = "+x);
count++;
cursor.moveToNext();
}
}
cursor.close();
CountryDB.close();
return count;
}
Make sure that database object is not null and your table is created first and column data type is integer . If you are putting string data then use getString(0);
this code is working fine for me.

Related

Android Studio: Unable to print cursor results

I am attempting to print the cursor results to log.d.
When I print the results of the cursor, it does not print the array.
i.e. D/Row values: com.example.androidlabs.Todo#7c9655f
Here is the code:
public void printCursor(Cursor c) {
//The database version number using db.getVersion for the version number.
int version = db.getVersion();
//The number of rows in the cursor
int rowCount = c.getCount();
//The number of columns in the cursor
int columnCount = c.getColumnCount();
//The names of the columns in the cursor
String[] columnNames = c.getColumnNames();
//The results of each row in the cursor
ArrayList<Todo> rowValuesList = new ArrayList<>();
int ColIndex = c.getColumnIndex(myOpener.COL_1);
int itemColIndex = c.getColumnIndex(myOpener.COL_2);
int urgentColIndex = c.getColumnIndex(myOpener.COL_3);
c.moveToFirst();
if(c.moveToFirst()) {
long id = c.getLong(ColIndex);
String item = c.getString(itemColIndex);
int urgentInt = c.getInt(urgentColIndex);
if (urgentInt == 1) {
urgent = true;
} else {
urgent = false;
}
rowValuesList.add(new Todo(item, urgent, id));
}
String rowValues = TextUtils.join(",", rowValuesList);
//Printing variables to log
Log.d("Database version", String.valueOf(version));
Log.d("Row count", String.valueOf(rowCount));
Log.d("Column count", String.valueOf(columnCount));
Log.d("Column names", Arrays.toString(columnNames));
Log.d("Row values", rowValues);
}
Other options I have tried that have not worked:
Log.d("Row values", rowValuesList.toString());
for (Todo t : rowValuesList) {
Log.d("Row values", String.valueOf(t));
}
StringBuilder s = new StringBuilder();
for(Todo todo : rowValuesList) {
s.append(todo);
s.append(",");
}
Log.d("Row values", String.valueOf(s));
I know the cursor is not empty as it is displays the results when loaded from SQLite on the application.
Any advice would be helpful.
Thank you,
Your output is:
D/Row values: com.example.androidlabs.Todo#7c9655f
That would make sense if:
rowValuesList contains a single Todo object, and
Your Todo class does not have a custom implementation of toString()
The default implementation of toString() that you inherit from Object gives a result like what you see: the fully qualified class name and an object ID, separated by #.

Android sqlite how to check if a record exists

I would like to check whether a record exists or not.
Here is what I've tried:
MainActivity.class
public void onTextChanged(CharSequence s, int start, int before, int count) {
System.out.println("Ontext changed " + new String(s.toString()));
strDocumentFrom = s.toString();
if(s.toString().isEmpty()){
} else {
try{
strTransactionDate = dbHelper.getTransactionDateByDocumentNumber(strDocumentFrom);
//strTotalAmount = dbHelper.getTotalAmountByDocumentNumber(strDocumentFrom);
//strVan = dbHelper.getVanByDocumentNumber(strDocumentFrom);
//etTransactionDate.setText(strTransactionDate);
//etTotalAmount.setText(strTotalAmount);
//Log.d("Van", "" + strVan);
//etVan.setText(strVan);
} catch (SQLiteException e) {
e.printStackTrace();
Toast.makeText(ReceivingStocksHeader.this,
"Document number does not exist.", Toast.LENGTH_SHORT).show();
}
}
DBHelper.class
// TODO DISPLAYING RECORDS TO TRANSRCVHEADER
public String getTransactionDateByDocumentNumber(String strDocumentNumber){
String[] columns = new String[]{KEY_TRANSACTIONDATE};
Cursor c = myDataBase.query(TBL_INTRANS,
columns, null,
null, null, null, null, null);
if(c != null){
c.moveToFirst();
String date = c.getString(0);
return date;
} else {
Log.d("Error", "No record exists");
}
return null;
}
But it doesn't get it to the catch block to display the toast.
What am I doing wrong in here?
public static boolean CheckIsDataAlreadyInDBorNot(String TableName,
String dbfield, String fieldValue) {
SQLiteDatabase sqldb = EGLifeStyleApplication.sqLiteDatabase;
String Query = "Select * from " + TableName + " where " + dbfield + " = " + fieldValue;
Cursor cursor = sqldb.rawQuery(Query, null);
if(cursor.getCount() <= 0){
cursor.close();
return false;
}
cursor.close();
return true;
}
I hope this is useful to you...
This function returns true if record already exists in db. Otherwise returns false.
These are all good answers, however many forget to close the cursor and database. If you don't close the cursor or database you may run in to memory leaks.
Additionally: You can get an error when searching by String that contains non alpha/numeric characters. For example: "1a5f9ea3-ec4b-406b-a567-e6927640db40". Those dashes (-) will cause an unrecognized token error. You can overcome this by putting the string in an array. So make it a habit to query like this:
public boolean hasObject(String id) {
SQLiteDatabase db = getWritableDatabase();
String selectString = "SELECT * FROM " + _TABLE + " WHERE " + _ID + " =?";
// Add the String you are searching by here.
// Put it in an array to avoid an unrecognized token error
Cursor cursor = db.rawQuery(selectString, new String[] {id});
boolean hasObject = false;
if(cursor.moveToFirst()){
hasObject = true;
//region if you had multiple records to check for, use this region.
int count = 0;
while(cursor.moveToNext()){
count++;
}
//here, count is records found
Log.d(TAG, String.format("%d records found", count));
//endregion
}
cursor.close(); // Dont forget to close your cursor
db.close(); //AND your Database!
return hasObject;
}
Raw queries are more vulnerable to SQL Injection. I will suggest using query() method instead.
public boolean Exists(String searchItem) {
String[] columns = { COLUMN_NAME };
String selection = COLUMN_NAME + " =?";
String[] selectionArgs = { searchItem };
String limit = "1";
Cursor cursor = db.query(TABLE_NAME, columns, selection, selectionArgs, null, null, null, limit);
boolean exists = (cursor.getCount() > 0);
cursor.close();
return exists;
}
Source: here
SELECT EXISTS with LIMIT 1 is much faster.
Query Ex: SELECT EXISTS (SELECT * FROM table_name WHERE column='value' LIMIT 1);
Code Ex:
public boolean columnExists(String value) {
String sql = "SELECT EXISTS (SELECT * FROM table_name WHERE column='"+value+"' LIMIT 1)";
Cursor cursor = database.rawQuery(sql, null);
cursor.moveToFirst();
// cursor.getInt(0) is 1 if column with value exists
if (cursor.getInt(0) == 1) {
cursor.close();
return true;
} else {
cursor.close();
return false;
}
}
You can use SELECT EXISTS command and execute it for a cursor using a rawQuery,
from the documentation
The EXISTS operator always evaluates to one of the integer values 0
and 1. If executing the SELECT statement specified as the right-hand
operand of the EXISTS operator would return one or more rows, then the
EXISTS operator evaluates to 1. If executing the SELECT would return
no rows at all, then the EXISTS operator evaluates to 0.
I have tried all methods mentioned in this page, but only below method worked well for me.
Cursor c=db.rawQuery("SELECT * FROM user WHERE idno='"+txtID.getText()+"'", null);
if(c.moveToFirst())
{
showMessage("Error", "Record exist");
}
else
{
// Inserting record
}
One thing the top voted answer did not mention was that you need single quotes, 'like this', around your search value if it is a text value like so:
public boolean checkIfMyTitleExists(String title) {
String Query = "Select * from " + TABLE_NAME + " where " + COL1 + " = " + "'" + title + "'";
Cursor cursor = database.rawQuery(Query, null);
if(cursor.getCount() <= 0){
cursor.close();
return false;
}
cursor.close();
return true;
}
Otherwise, you will get a "SQL(query) error or missing database" error like I did without the single quotes around the title field.
If it is a numeric value, it does not need single quotes.
Refer to this SQL post for more details
SQLiteDatabase sqldb = MyProvider.db;
String Query = "Select * from " + TABLE_NAME ;
Cursor cursor = sqldb.rawQuery(Query, null);
cursor.moveToLast(); //if you not place this cursor.getCount() always give same integer (1) or current position of cursor.
if(cursor.getCount()<=0){
Log.v("tag","if 1 "+cursor.getCount());
return false;
}
Log.v("tag","2 else "+cursor.getCount());
return true;
if you not use cursor.moveToLast();
cursor.getCount() always give same integer (1) or current position of cursor.
Code :
private String[] allPushColumns = { MySQLiteHelper.COLUMN_PUSH_ID,
MySQLiteHelper.COLUMN_PUSH_TITLE, MySQLiteHelper.COLUMN_PUSH_CONTENT, MySQLiteHelper.COLUMN_PUSH_TIME,
MySQLiteHelper.COLUMN_PUSH_TYPE, MySQLiteHelper.COLUMN_PUSH_MSG_ID};
public boolean checkUniqueId(String msg_id){
Cursor cursor = database.query(MySQLiteHelper.TABLE_PUSH,
allPushColumns, MySQLiteHelper.COLUMN_PUSH_MSG_ID + "=?", new String [] { msg_id }, null, null, MySQLiteHelper.COLUMN_PUSH_ID +" DESC");
if(cursor.getCount() <= 0){
return false;
}
return true;
}
Here's a simple solution based on a combination of what dipali and Piyush Gupta posted:
public boolean dbHasData(String searchTable, String searchColumn, String searchKey) {
String query = "Select * from " + searchTable + " where " + searchColumn + " = ?";
return getReadableDatabase().rawQuery(query, new String[]{searchKey}).moveToFirst();
}
because of possible data leaks best solution via cursor:
Cursor cursor = null;
try {
cursor = .... some query (raw or not your choice)
return cursor.moveToNext();
} finally {
if (cursor != null) {
cursor.close();
}
}
1) From API KITKAT u can use resources try()
try (cursor = ...some query)
2) if u query against VARCHAR TYPE use '...' eg. COLUMN_NAME='string_to_search'
3) dont use moveToFirst() is used when you need to start iterating from beggining
4) avoid getCount() is expensive - it iterates over many records to count them. It doesn't return a stored variable. There may be some caching on a second call, but the first call doesn't know the answer until it is counted.
Try to use cursor.isNull method.
Example:
song.isFavorite = cursor.isNull(cursor.getColumnIndex("favorite"));
You can use like this:
String Query = "Select * from " + TABLE_NAME + " where " + Cust_id + " = " + cust_no;
Cursor cursorr = db.rawQuery(Query, null);
if(cursor.getCount() <= 0){
cursorr.close();
}
cursor.close();
private boolean checkDataExistOrNot(String columnName, String value) {
SQLiteDatabase sqLiteDatabase = getReadableDatabase();
String query = "SELECT * FROM" + TABLE_NAME + " WHERE " + columnName + " = " + value;
Cursor cursor = sqLiteDatabase.rawQuery(query, null);
if (cursor.getCount() <= 0) {
cursor.close();
return false; // return false if value not exists in database
}
cursor.close();
return true; // return true if value exists in database
}
I prefer to do it this way because it's fast and less expensive than other methods:
Cursor cursor = db.rawQuery("SELECT 1 FROM table WHERE condition = 1 LIMIT 1", null);
try {
if (cursor.moveToNext()) {
//Record exists
} else {
//Record doesn't exists
}
} finally {
cursor.close();
}
My version:
public boolean isTitleExists(String title, String type) {
int isExists = 0;
try {
String query = "SELECT EXISTS (SELECT 1 FROM titles WHERE title = ? and type = ?)";
PreparedStatement statement = connection.prepareStatement(query);
statement.setString(1, title);
statement.setString(2, type);
ResultSet rs = statement.executeQuery();
rs.next();
isExists = rs.getInt(1);
rs.close();
statement.close();
} catch (SQLException e) {
Common.console("isTitleExists error: " + e.getMessage());
}
return isExists == 1;
}

simple select query arguments passing issue

I am new with android.
I just wanted to take the count of number of rows in table against particular user in DB (uid is column in db).
For this purpose i made following function:
public int getCount(int uid)
{
String query = "select count(*) from "+TABLE_MESSAGES+ " WHERE uid=?";
Cursor c = ourDB.rawQuery(query,uid);
}
But its giving me error:
The method rawQuery(String, String[]) in the type SQLiteDatabase is
not applicable for the arguments (String, int)
also want to know how can i be able to return count from this?
Please help me.
you should use this WAY:
public int getCount(int uid)
{
String query = "select count(*) from "+TABLE_MESSAGES+ " WHERE uid="+uid+"";
Cursor c = ourDB.rawQuery(query,null);
if(c.getCount()>0)
c.moveToFirst();
do{
int id = c.getInt(0);
}while(c.moveToNext());
}
Try this way
public int getCount(int uid){
try{
String query = "select count(*)'count' from "+TABLE_MESSAGES+ " WHERE uid="+uid+"";
Cursor c = ourDB.rawQuery(query,null);
if (c.moveToFirst()) {
return Integer.parseInt(cursor.getString(0));
}
}catch (Throwable e) {
e.printStackTrace();
}
return 0;
}
change your query to:
String query = "select count(*) from "+TABLE_MESSAGES+ " WHERE uid="+uid;
Cursor c = ourDB.rawQuery(query);
The method rawQuery(String, String[]) in the type SQLiteDatabase is
not applicable for the arguments (String, int)
Clearly states you are passing int instead of expected String[]
Cursor c = ourDB.rawQuery(query,new String[]{ uid });
use the query as :
"SELECT * FROM <DB_NAME> WHERE uid="+uid
and then use the getCount() method on the cursor
like :
Cursor csr = db.rawQuery("above query string here");
int count = csr.getCount();

How to get row count in sqlite using Android?

I am creating task manager. I have tasklist and I want when I click on particular tasklist name if it empty then it goes on Add Task activity but if it has 2 or 3 tasks then it shows me those tasks into it in list form.
I am trying to get count in list. my database query is like:
public Cursor getTaskCount(long tasklist_Id) {
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor= db.rawQuery("SELECT COUNT (*) FROM " + TABLE_TODOTASK + " WHERE " + KEY_TASK_TASKLISTID + "=?",
new String[] { String.valueOf(tasklist_Id) });
if(cursor!=null && cursor.getCount()!=0)
cursor.moveToNext();
return cursor;
}
In My activity:
list_tasklistname.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0,
android.view.View v, int position, long id) {
db = new TodoTask_Database(getApplicationContext());
Cursor c = db.getTaskCount(id);
System.out.println(c.getCount());
if(c.getCount()>0) {
System.out.println(c);
Intent taskListID = new Intent(getApplicationContext(), AddTask_List.class);
task = adapter.getItem(position);
int taskList_id = task.getTaskListId();
taskListID.putExtra("TaskList_ID", taskList_id);
startActivity(taskListID);
}
else {
Intent addTask = new Intent(getApplicationContext(), Add_Task.class);
startActivity(addTask);
}
}
});
db.close();
}
but when I am clicking on tasklist name it is returning 1, bot number of tasks into it.
Using DatabaseUtils.queryNumEntries():
public long getProfilesCount() {
SQLiteDatabase db = this.getReadableDatabase();
long count = DatabaseUtils.queryNumEntries(db, TABLE_NAME);
db.close();
return count;
}
or (more inefficiently)
public int getProfilesCount() {
String countQuery = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
int count = cursor.getCount();
cursor.close();
return count;
}
In Activity:
int profile_counts = db.getProfilesCount();
db.close();
Use android.database.DatabaseUtils to get number of count.
public long getTaskCount(long tasklist_Id) {
return DatabaseUtils.queryNumEntries(readableDatabase, TABLE_NAME);
}
It is easy utility that has multiple wrapper methods to achieve database operations.
c.getCount() returns 1 because the cursor contains a single row (the one with the real COUNT(*)). The count you need is the int value of first row in cursor.
public int getTaskCount(long tasklist_Id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor= db.rawQuery(
"SELECT COUNT (*) FROM " + TABLE_TODOTASK + " WHERE " + KEY_TASK_TASKLISTID + "=?",
new String[] { String.valueOf(tasklist_Id) }
);
int count = 0;
if(null != cursor)
if(cursor.getCount() > 0){
cursor.moveToFirst();
count = cursor.getInt(0);
}
cursor.close();
}
db.close();
return count;
}
I know it is been answered long time ago, but i would like to share this also:
This code works very well:
SQLiteDatabase db = this.getReadableDatabase();
long taskCount = DatabaseUtils.queryNumEntries(db, TABLE_TODOTASK);
BUT what if i dont want to count all rows and i have a condition to apply?
DatabaseUtils have another function for this: DatabaseUtils.longForQuery
long taskCount = DatabaseUtils.longForQuery(db, "SELECT COUNT (*) FROM " + TABLE_TODOTASK + " WHERE " + KEY_TASK_TASKLISTID + "=?",
new String[] { String.valueOf(tasklist_Id) });
The longForQuery documentation says:
Utility method to run the query on the db and return the value in the first column of the first row.
public static long longForQuery(SQLiteDatabase db, String query, String[] selectionArgs)
It is performance friendly and save you some time and boilerplate code
Hope this will help somebody someday :)
Change your getTaskCount Method to this:
public int getTaskCount(long tasklist_id){
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor= db.rawQuery("SELECT COUNT (*) FROM " + TABLE_TODOTASK + " WHERE " + KEY_TASK_TASKLISTID + "=?", new String[] { String.valueOf(tasklist_id) });
cursor.moveToFirst();
int count= cursor.getInt(0);
cursor.close();
return count;
}
Then, update the click handler accordingly:
public void onItemClick(AdapterView<?> arg0, android.view.View v, int position, long id) {
db = new TodoTask_Database(getApplicationContext());
// Get task list id
int tasklistid = adapter.getItem(position).getTaskListId();
if(db.getTaskCount(tasklistid) > 0) {
System.out.println(c);
Intent taskListID = new Intent(getApplicationContext(), AddTask_List.class);
taskListID.putExtra("TaskList_ID", tasklistid);
startActivity(taskListID);
} else {
Intent addTask = new Intent(getApplicationContext(), Add_Task.class);
startActivity(addTask);
}
}
In order to query a table for the number of rows in that table, you want your query to be as efficient as possible. Reference.
Use something like this:
/**
* Query the Number of Entries in a Sqlite Table
* */
public long QueryNumEntries()
{
SQLiteDatabase db = this.getReadableDatabase();
return DatabaseUtils.queryNumEntries(db, "table_name");
}
Do you see what the DatabaseUtils.queryNumEntries() does? It's awful!
I use this.
public int getRowNumberByArgs(Object... args) {
String where = compileWhere(args);
String raw = String.format("SELECT count(*) FROM %s WHERE %s;", TABLE_NAME, where);
Cursor c = getWriteableDatabase().rawQuery(raw, null);
try {
return (c.moveToFirst()) ? c.getInt(0) : 0;
} finally {
c.close();
}
}
Sooo simple to get row count:
cursor = dbObj.rawQuery("select count(*) from TABLE where COLUMN_NAME = '1' ", null);
cursor.moveToFirst();
String count = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(0)));
looking at the sources of DatabaseUtils we can see that queryNumEntries uses a select count(*)... query.
public static long queryNumEntries(SQLiteDatabase db, String table, String selection,
String[] selectionArgs) {
String s = (!TextUtils.isEmpty(selection)) ? " where " + selection : "";
return longForQuery(db, "select count(*) from " + table + s,
selectionArgs);
}
Once you get the cursor you can do
Cursor.getCount()

Database retrieval in android

In my application i am showing data from database in a table view.My requirement is that from database i have to retrieve the data which will fall in the current month.I Have written the query but it is coming as 0.Actually i have 1 entry in the database with today's date,so my query should return that data,but it is showing as 0.Please help me.Thanks in advance.
My query is as follows:
public String addgroupincome(String grp) throws SQLException
{
long sum=0;
Cursor cursor1 = db.rawQuery(
"SELECT SUM("+(KEY_TOTAL)+") FROM incomexpense WHERE date= Strftime('%Y-%m','now') AND category='Income' AND groups='"+grp+"'",null);
if(cursor1.moveToFirst())
{
sum = cursor1.getLong(0);
}
cursor1.close();
String housetotal=String.valueOf((long)sum);
return housetotal;
}
I am getting that total and showing in atextview in table layout..
final String houtotal=db.addgroupincome(group1);
housetotal.setText(houtotal);
Most probably nothing wrong with the query but the way you pass the query result to ListView. Can you show how you do it? Perhaps I could help.
Or you could take a look here or here
public int getCount() {
DBHelper dbHelper = DBHelper.getDBAdapterInstance(this);
int count = 0;
try {
dbHelper.openDataBase();
String query = "select count(1) from t_model where upper(brandName) = upper('"
+ selectedBrand + "') order by modelName ASC";
Cursor cursor = dbHelper.selectRecordsCursor(query, null);
if (cursor.moveToFirst()) {
count = cursor.getInt(0);
}
cursor.close();
cursor = null;
} catch (Exception e) {
e.printStackTrace();
} finally {
dbHelper.close();
}
return count;
}
and for the TextView should be as simple as
TextView tvCount = (TextView) findViewById(R.id.tvCount);
tvCount.setText("Count : " + getCount);
If you are having trouble debugging your query. Try http://sqlitebrowser.sourceforge.net/ or http://www.sqliteexpert.com/
Why don't you try by giving column names of your table in your query..might it work out for you..specify the columns which you want to retrive..
if (cursor.moveToNext()) {
cursor.moveToFirst();
while (cursor.isAfterLast() == false) {
Log.i(ID, cursor.getInt(0) + "");
cursor.moveToNext();
}
cursor.close();
} else {
cursor.close();
return null;
}
Try This Method....

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