I am implementing an SQLite database and I can not figure out why some column values are null. Here is where I am writing to my SQLiteDatabase(db). The ArrayList DEFINITELY has the list of vehicles and each vehicle DEFINITELY has the correct values in it(Vehicle ID, address, city, state....). The table inside of the database also has the columns that i constructed(I checked this as well).
For some reason when I am doing a call like cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_CITY)) it is getting null but when I do the same call but to KEY_LAT, it works. (Vehicle ID, Lat and Lon work, but the others do not)..
public static void addVehicle(ArrayList<Vehicle> aList) {
Database.openWritable();
ContentValues values = new ContentValues();
for(Vehicle vehicle : aList){
values.put(KEY_VEHICLE_ID, vehicle.getvehicleID());
values.put(KEY_ADDRESS, vehicle.getaddress());
values.put(KEY_CITY, vehicle.getcity());
values.put(KEY_STATE, vehicle.getstate());
values.put(KEY_LAT, vehicle.getLat());
values.put(KEY_LON, vehicle.getLon());
db.insert(TABLE_VEHICLE, null, values);
}
}
Additional Information/Question This do loop is happening like hundreds of times and i feel like it should only be happening for the number of rows i have, which is 14(i have 14 vehicles in the database). This may be affecting something? But i suspect not. So why is this happening? :
String query = "SELECT * FROM " + DatabaseHandler.TABLE_VEHICLE;
Cursor cursor = Database.listOfVehiclesDesired(query);
String lat = "";
String lon = "";
String title = "";
String snippet = "";
if(cursor.moveToFirst()){
do {
lat = (cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_LAT)));
lon = (cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_LON)));
title = cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_VEHICLE_ID)) + " " + cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_VEHICLE_NAME));
snippet = "City:" + cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_CITY)) + ", State: " + cursor.getString(cursor.getColumnIndex(DatabaseHandler.KEY_STATE));
addMarkers(new LatLng(lat, lon), true, R.drawable.cap, title, snippet);
} while (cursor.moveToNext());
}
if (cursor != null && !cursor.isClosed()) {
cursor.close();
}
Superfluous(?) BACKGROUND INFROMATION: I am using a static class to access the SQLiteDatabase, also, this code of getting column index and such is in an AsyncTask.
how you close cursor if cursor is closed ?!!
you code :
if (cursor != null && !cursor.isClosed()) {
cursor.close();
try the code with just cursor.close();
Related
I am retrieving data according to dates but when running my app its shows nothing.
Here's my code :
SQL QUERY :
private Cursor getAllCurrentData()
{
String[] selectArg = new String[]{};
return db.query(Db_Contract.Db_Fieds.TABLE_NAME,
null ,
Db_Contract.Db_Fieds.DATE+ "= 2018-11-10",
selectArg,
null,
null,
Db_Contract.Db_Fieds.TIMESTAMP);
}
Displaying Data :
private void totalMoney()
{
Cursor cursor = getAllCurrentData();
double sum = 0.000d;
double getMoney;
while (cursor.moveToNext()) {
getMoney = cursor.getDouble(cursor.getColumnIndex(Db_Contract.Db_Fieds.MONEY));
sum += getMoney;
}
total.setText("Total money spent: " +sum);
}
I am new to Android Programming. Where I am doing wrong ?. Please correct me
First make sure you are connected to database and cursor returned by db.query() is not empty/null. Then Iterate over cursor like
private void totalMoney()
{
openDatabase();
Cursor cursor = getAllCurrentData();
cursor.moveToFirst();
double getMoney = 0;
while (!cursor.isAfterLast()) {
getMoney = cursor.getDouble(cursor.getColumnIndex(Db_Contract.Db_Fieds.MONEY));
sum += getMoney;
cursor.moveToNext();
}
total.setText("Total money spent: " + sum );
closeDatabase();
}
I have two method's in my SQLite Database in which i check if there is in a table certain column that is the same as a String after it i print all other columns on the same row and with the second method i check if a column from the first method equals to a data stored in a column of another table.
But i'm having issues when i check for a data that is not in the database here is an example:
TABLE CODART_BARCODE
CODART_CODART CODART_BARCODE CODART_PXC
123 1234 1
TABLE CODART_ART
DESCR_ART PVEN_ART PACQ_ART CODART_ART
PIZZ 1.50 12 123
So if in an EditText i insert 123 that equals to CODART_CODART and there is also 123 in CODART_ART from the other table i will print "PIZZ 1.50 12" but if i insert in the EditText 12356 the app crash because there is no same data in DB how can i prevent that app crash? i mean if there is no same data can i make a Toast that says "no data" or something like this but not making the app crash?
Here are the two methods from DB:
public String dbRawSearch(String id) {
StringBuilder dbString = new StringBuilder();
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT * FROM " + TABLE_CODART + " WHERE CODART_BARCODE = " + id;
//Cursor points to a location in your results
#SuppressLint("Recycle") Cursor c = db.rawQuery(query, null);
//Move to the first row in your results
c.moveToFirst();
//Position after the last row means the end of the results
while (!c.isAfterLast()) {
if (c.getString(c.getColumnIndex("CODART_BARCODE")) != null) {
dbString.append(c.getString(c.getColumnIndex("CODART_CODART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_BARCODE"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_PXC"))).append("\n");
}
c.moveToNext();
}
db.close();
return dbString.toString();
}
// FETCH codArt from Articoli
public String dbRawArticoli(String id){
StringBuilder dbString = new StringBuilder();
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT * FROM " + TABLE_ART + " WHERE CODART_ART = " + id;
Cursor c = db.rawQuery(query, null);
c.moveToFirst();
while (!c.isAfterLast()) {
if (c.getString(c.getColumnIndex("CODART_ART")) != null) {
dbString.append(c.getString(c.getColumnIndex("DESCR_ART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("PVEN_ART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("PACQ_ART"))).append("\n");
}
c.moveToNext();
}
db.close();
return dbString.toString();
}
Your issue is that you are not correctly enclosing the search argument and thus if the value is non numeric then SQLite will consider that you are comparing a column, hence the no column found.
Lets say assuming you use :-
String result1 = yourdbHelper.dbRawSearch("123");
Then the resultant SQL will be :-
SELECT * FROM CODART WHERE CODART_BARCODE = 123;
That is fine as the search is looking for a number.
However if you used:-
String result1 = yourdbHelper.dbRawSearch("Fred");
Then the resultant SQL will be :-
SELECT * FROM CODART WHERE CODART_BARCODE = FRED
This would fail because FRED is non-numeric, and is therefore interpreted as saying SELECT all columns from the table CODART where the column named COADRT has the same value as the column named FRED, there is no column named FRED.
The result is that you get an error along the lines of :-
06-11 11:34:12.653 1373-1373/soanswers.soanswers E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{soanswers.soanswers/soanswers.soanswers.MainActivity}: android.database.sqlite.SQLiteException: no such column: FRED (code 1): , while compiling: SELECT * FROM CODART WHERE CODART_BARCODE = FRED
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
at android.app.ActivityThread.access$600(ActivityThread.java:130)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
The Fix
The resolution is simple, and that is to enclose the argument being searched for in single quotes so that the SQL is then :-
SELECT * FROM CODART WHERE CODART_BARCODE = 'FRED'
Note that is just one example. However you will need to makes similar changes to both methods (dbRawSearch and dbRawArticoli), as shown :-
To do this you could change :-
String query = "SELECT * FROM " + TABLE_CODART + " WHERE CODART_BARCODE = " + id;
to :-
String query = "SELECT * FROM " + TABLE_CODART + " WHERE CODART_BARCODE = '" + id + "'";
and also change :-
String query = "SELECT * FROM " + TABLE_ART + " WHERE CODART_ART = " + id;
to :-
String query = "SELECT * FROM " + TABLE_ART + " WHERE CODART_ART = '" + id + "'";
Additional
However, there are SQLiteDatabase convenience methods that simplify building queries which also enclose/convert data accordingly.
One of these is the query method (as used in the following).
Rather than
moving to the first row and then
checking to see if you are then at the last row and then
using a moveToNext then going back to 2
in a do while loop, as all of the Cursor move??? methods return
true if the move could be made
otherwise false
you can simplify matters using :-
while(yourcursor.moveToNext) {
.... process the current row
}
As such the following methods could be considered
Note the 2 at the end of the method name is just to distinguish them from the originals
:-
public String dbRawSearch2(String id) {
StringBuilder dbString = new StringBuilder();
String whereclause = "CODART_BARCODE=?";
String[] whereargs = new String[]{id};
SQLiteDatabase db = this.getWritableDatabase();
Cursor c = db.query(TABLE_CODART,null,whereclause,whereargs,null,null,null);
while (c.moveToNext()) {
dbString.append(c.getString(c.getColumnIndex("CODART_CODART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_BARCODE"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_PXC"))).append("\n");
}
c.close(); //<<<< Should always close cursors when finished with them
db.close();
return dbString.toString();
}
public String dbRawArticoli2(String id) {
StringBuilder dbString = new StringBuilder();
String whereclause = "CODART_ART=?";
String[] whereargs = new String[]{id};
SQLiteDatabase db = this.getWritableDatabase();
Cursor c= db.query(TABLE_ART,null,whereclause,whereargs,null,null,null);
while (c.moveToNext()) {
dbString.append(c.getString(c.getColumnIndex("DESCR_ART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("PVEN_ART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("PACQ_ART"))).append("\n");
}
c.close();
db.close();
return dbString.toString();
}
you should use wether your cursor is null or not and its size
if (c != null) {
if (c.getCount() > 0) {
return "your string";
}
}
return "";// In case no record found
In blank case give proper msg to the end user.
Change this part :
//Move to the first row in your results
c.moveToFirst();
//Position after the last row means the end of the results
while (!c.isAfterLast()) {
if (c.getString(c.getColumnIndex("CODART_BARCODE")) != null) {
dbString.append(c.getString(c.getColumnIndex("CODART_CODART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_BARCODE"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_PXC"))).append("\n");
}
c.moveToNext();
}
To :
//Move to the first row in your results
if(c!= null && c.moveToFirst())
{
//Position after the last row means the end of the results
while (!c.isAfterLast()) {
if (c.getString(c.getColumnIndex("CODART_BARCODE")) != null) {
dbString.append(c.getString(c.getColumnIndex("CODART_CODART"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_BARCODE"))).append("\n");
dbString.append(c.getString(c.getColumnIndex("CODART_PXC"))).append("\n");
}
c.moveToNext();
}
}
Explanation: In the case where there is no same data available you don't have the result set to get the string or column index from the result set.
I have to insert a lot of rows in my SQLite Database and for some tables
a specific value of each row has to be converted into an other using the value of an other table.
Actually, I have this function which is working well:
public void myFunction( String tableName, String attrName, ContentValues currentVal ) {
SQLiteDatabase database = this.getReadableDatabase();
Cursor c = database.rawQuery("SELECT colName FROM "+tableName+" WHERE "+tableName+".otherColName = " + currentVal.getAsString(attrName), null);
Long realValue = null;
if( c.moveToFirst() ) {
realValue = c.getLong(0);
}
if( c != null ) c.close();
currentVal.put( attrName, realValue );
}
But, this is really time consumimg because of this part:
if( c.moveToFirst() ) {
realValue = c.getLong(0);
}
So I wanted to know if there's a way to set the query directly in the value of the ContantValue like this:
currentVal.put( attrName, "SELECT colName FROM "+tableName+" WHERE "+tableName+".otherColName = " + currentVal.getAsString(attrName));
and the query will be executed at the same time as the insert query in order to replace the value.
Thank you beforehand!
No, ContentValues is just a wrapper of a hash map for the data. You can try to use index to accelerate the query.
I'm trying to read data from newly deleted SQLite db table row.
Basically my program will delete a row when a certain activity is loaded, and I want to check the value inside the row.
This is my get code :
public String getSlot() {
String slots = new String();
Cursor cursor = database.query(ChosenSlotDatabaseHandler.TABLE_CHOSEN_PARKING_SLOT,
chosenSlotColumn, null, null, null, null, null);
if( cursor.moveToFirst() ) {
slots = cursor.getString(0);
}
// make sure to close the cursor
cursor.close();
return slots;
}
I've used these codes to delete the value :
public static final String DELETE_SLOT = "DELETE FROM "
+ TABLE_CHOSEN_PARKING_SLOT + " WHERE "
+ "_ID = " + CHOSEN_ID + ";";
public void deleteSlotSQL()
{
database.execSQL(ChosenSlotDatabaseHandler.DELETE_SLOT);
}
And this is my condition to set a TextViewvalue :
if(slots == null)
{
chosenSlotView.setText("You have not parked");
}
else
{
chosenSlotView.setText("You are parked in : " + slots);
}
At first, I thought that once the only row is deleted, getSlot() would return null, but it seems that it's not null from this Log.d I ran :
if(slots != null)
{
Log.d("notnull","not null dude");
}else
{
Log.d("null","Yay null");
}
The log returns "not null dude"..
Any suggestion on how to get the slots value so I can set the TextView value??
your slots definitely not null because of this :
String slots = new String();
it should be
String slots = null;
Cursor cursor = database.query(ChosenSlotDatabaseHandler.TABLE_CHOSEN_PARKING_SLOT,
chosenSlotColumn, null, null, null, null, null);
if( cursor.moveToFirst() ) {
slots = cursor.getString(0);
}
// make sure to close the cursor
cursor.close();
return slots;
EDIT :
Nevermind that String slot = null,
Try using :
if(slots.isEmpty())
{
chosenSlotView.setText(notParked);
}
else
{
chosenSlotView.setText(isParked + slots);
}
First off all you should avoid using logs like "not null dude", you will find them funny and suggestive but after a while we won t be able to write clean and professional code.
My second advice is to use constants instead of hadcoded strings . Create a class Constants and add there strings
public static final String NOT_PARKED = "You have not parked"
My third advice is to take a look at ormlite http://logic-explained.blogspot.ro/2011/12/using-ormlite-in-android-projects.html
If the logs are ok , maybe there is a problem with textview . Try putting a text in textview before the condition to check if will get set . Check the layout file also .
I'm not sure what I'm doing wrong, but I'm trying to update a single integer value in a column of a table to 1 from 0. When creating the database, I set all values of the column to zero using:
for (int i = 0; i < setups.length; i++) {
ContentValues values = new ContentValues();
values.put(JokeDbContract.TblJoke.COLUMN_NAME_SETUP, setups[i]);
values.put(JokeDbContract.TblJoke.COLUMN_NAME_PUNCHLINE, punchlines[i]);
values.put(JokeDbContract.TblJoke.COLUMN_NAME_USED, 0);
db.insert(JokeDbContract.TblJoke.TABLE_NAME, null, values);
}
Then, in the actual activity, I'm doing:
private void findNewJoke() {
JokeDb jokeDb = JokeDb.getInstance(this);
SQLiteDatabase theDb = jokeDb.getDB();
String selection = JokeDbContract.TblJoke.COLUMN_NAME_USED + "=" + 0;
// Query database for a joke that has not been used, update the fields
// theJoke and thePunchline appropriately
String[] columns = {JokeDbContract.TblJoke._ID,
JokeDbContract.TblJoke.COLUMN_NAME_PUNCHLINE,
JokeDbContract.TblJoke.COLUMN_NAME_SETUP,
JokeDbContract.TblJoke.COLUMN_NAME_USED};
Cursor c = theDb.query(JokeDbContract.TblJoke.TABLE_NAME, columns, selection,
null, null, null, null);
if (c.moveToFirst() == false) {
Toast.makeText(this, R.string.error_retrieving_joke, Toast.LENGTH_LONG).show();
Log.e(getString(R.string.app_name),"No jokes retreived from DB in JokeActivity.findNewJoke()!");
}
else {
ContentValues values = new ContentValues();
theSetup = c.getString(c.getColumnIndexOrThrow(JokeDbContract.TblJoke.COLUMN_NAME_SETUP));
thePunchline = c.getString(c.getColumnIndexOrThrow(JokeDbContract.TblJoke.COLUMN_NAME_PUNCHLINE));
String updateSelection = JokeDbContract.TblJoke.COLUMN_NAME_SETUP + "=" + theSetup;
values.put(JokeDbContract.TblJoke.COLUMN_NAME_USED, 1);
theDb.update(JokeDbContract.TblJoke.TABLE_NAME, values, updateSelection, null);
}
}
I'm getting an error on the update:
java.lang.RuntimeException: .... while compiling: UPDATE jokes SET used=?
WHERE setup=Why do programmers always mix up Halloween and Christmas?
It seems as though I'm not getting an actual value set for the used column. What the program ultimately does is cycle through jokes where used=0, then sets used to 1 when it has been viewed. So the query only pulls those jokes that aren't used yet. I have a feeling I'm missing something simple, one can hope.
I think you are having problems with quotation marks.
Example:
String updateSelection = JokeDbContract.TblJoke.COLUMN_NAME_SETUP + "=\"" + theSetup + "\"";
However, the recommended way to do this, would be:
theDb.update(JokeDbContract.TblJoke.TABLE_NAME, values, JokeDbContract.TblJoke.COLUMN_NAME_SETUP + " = ?", new String[] { theSetup });
It is better to use field = ?, because this helps sqlite cache queries (I believe).