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SQLite query give different result from mysql

I have two table in my sqlite db here is the first table named supplier and here is the second table named product
what I want to do is I want to get the supplier_name in table product by selecting id_supplier in table_product. Here is my query SELECT table_supplier.id_supplier, table_supplier.supplier_name from table_invoice_in, table_supplier where table_invoice_in.id_product = '4' and table_supplier.id_supplier = table_invoice_in.id_supplier
and what I got from that query is I can get the id_supplier but supplier_name gives me 0 value, but when I try the query in mysql, I got the correct result. My question is :
Is this a limitation of sqlite or there are something wrong with my query?
Thank you in advance.

Try using a JOIN:
SELECT table_supplier.id_supplier, table_supplier.supplier_name FROM table_supplier JOIN table_invoice_in ON table_supplier.id_supplier = table_invoice_in.id_supplier WHERE table_invoice_in.id_product = '4'

The problem solved! When we try to query some column(s) from multiple table, make sure that we get the desired result by pointing directly to the column name. Here is my correct code
public Cursor SelectInvoiceInById(String id){
String query = "SELECT product_name from table_product, table_invoice_in where table_invoice_in.id_invoice_in = '"+ id + "' and table_product.id_product = table_invoice_in.id_product";
ReadDB();
cursor = database.rawQuery(query, null);
cursor.moveToFirst();
if(cursor.getCount() > 0){
while (!cursor.isAfterLast()){
Log.d("RESULT", String.valueOf(cursor.getString(cursor.getColumnIndex(SQLiteHelper.PRODUCT_NAME))));
cursor.moveToNext();
}
}
CloseDB();
return cursor;
}

Android select statement returns no results via rawquery or query while using query directly works

I've spent the whole day so far trying to get a select query to execute viarawquery or query, but I've had no luck so far.
The select statement I want to run is as the following:
SELECT * FROM h_word WHERE category='GRE' AND DONE=0 ORDER BY RANDOM() LIMIT 1
category is a TEXT type column and DONE is an INTEGER type with the default value of 0.
While the query works fine when executed directly in SQLite, in android,it doesn't return any results.
I've tried the below with no luck (the method is located in a class extended from SQLiteAssetHelper which itself is a helper class originally extended from SQLiteOpenHelper originaly taken from here: https://github.com/jgilfelt/android-sqlite-asset-helper:
public Cursor getRandomWord() {
Cursor c;
SQLiteDatabase db = getWritableDatabase();
c=db.rawQuery(query, null);
String query = "SELECT * FROM h_word WHERE category='GRE' AND DONE='0'
ORDER BY RANDOM() LIMIT 1 ";
c=db.rawQuery(query, new String[] {});
c.moveToFirst();
db.close();
return c;
}
I also tested with GRE instead of 'GRE' and 0 instead of '0' but it made no difference.
did the following as well:
public Cursor getRandomWord() {
Cursor c;
SQLiteDatabase db = getReadableDatabase();
c=db.query(true, "h_word", new String[] {
"_id",
"word",
"english_meaning"
},
"category" + "=?" + " AND " +
"DONE" + "=?",
new String[]{"GRE" ,"0"},
null, null, "RANDOM() LIMIT 1" , null);
c.moveToFirst();
db.close();
return c;
}
but the cursor remains empty.
Any ideas what I might be doing wrong here?
Any help would be much appreciated.
PS: when running a simple select statement without a where clause it, works fine.

After another few hours of struggling, I figured it's a bug in android's SQLiteDatabase class.
I managed to solve the problem by changing the name of the "category" column to something else.
Seems like "category" is a key word in the android SQLiteDatabase code, and makes a query return nothing when written in where clauses on the android side.
Someone else also had this problem here:
Android rawquery with dynamic Where clause

Database retreival in android

I am retrieving data from database using select query.My requirement is i have to sum the (total) column where group=household and category=Income.I have 1 entry in database which satisfy this condition.But it returns always 0.Please help me.
My query is:
long sum=0;
Cursor cursor1 = db.rawQuery(
"SELECT SUM("+(KEY_TOTAL)+") FROM incomexpense WHERE groups='Household' & category='Income'",null);
if(cursor1.moveToFirst())
{
sum = cursor1.getLong(0);
}
cursor1.close();
String housetotal=String.valueOf((long)sum);
System.out.println("house="+housetotal);

Try replacing the & with AND in the query.

I guess the query might not have worked because you have written '&' instead of 'and'

Removing rows from an Android SQLite Cursor

I query and get a result set back, but I need to do some calculations that are impossible in the SQLite WHERE clause in order to determine what shows up in the ListView. How can I remove certain rows from the cursor? I know it is the same question as this Filter rows from Cursor so they don't show up in ListView but that answer does not help. Can an example be provided if there isn't a simpler way to do this?

It might work to simply retain all the rows in the Cursor, but then use a custom adapter to hide the unwanted rows at display time. For example, if you extend CursorAdapter, then you might have something like this in your bindView implementation:
View v = view.findViewById(R.id.my_list_entry);
boolean keepThisRow = .......; // do my calculations
v.setVisibility(keepThisRow ? View.VISIBLE : View.GONE);

There should be a better way to do this, but what I ended up doing is storing the ID of each row I wanted in a string ArrayList, and then requerying where _id IN arraListOfIds.toString(), replacing the square brackets with parentheses to fit SQL syntax.
// Get all of the rows from the database
mTasksCursor = mDbHelper.fetchAllTasks();
ArrayList<String> activeTaskIDs = new ArrayList<String>();
// calculate which ones belong
// .....
if (!hasCompleted)
activeTaskIDs.add(mTasksCursor.getString(TaskerDBadapter.INDEX_ID));
// requery on my list of IDs
mTasksCursor = mDbHelper.fetchActiveTasks(activeTaskIDs);
public Cursor fetchActiveTasks(ArrayList<String> activeTaskIDs)
{
String inClause = activeTaskIDs.toString();
inClause = inClause.replace('[', '(');
inClause = inClause.replace(']', ')');
Cursor mCursor = mDb.query(true, DATABASE_TABLE, columnStringArray(),
KEY_ROWID + " IN " + inClause,
null, null, null, null, null);
if (mCursor != null) { mCursor.moveToFirst(); }
return mCursor;
}

ContentResolver cr = getContentResolver();
Cursor groupCur = cr.query(
Groups.CONTENT_URI, // what table/content
new String [] {Groups._ID, Groups.NAME}, // what columns
"Groups.NAME NOT LIKE + 'System Group:%'", // where clause(s)
null, // ???
Groups.NAME + " ASC" // sort order
);
The "What Columns" piece above is where you can tell the cursor which rows to return. Using "null" returns them all.

I need to do some calculations that
are impossible in the SQLite WHERE
clause
I find this very hard to believe; my experience has been that SQL will let you query for just about anything you'd ever need (with the exception of heirarchical or recursive queries in SQLite's case). If there's some function you need that isn't supported, you can add it easily with sqlite_create_function() and use it in your app. Or perhaps a creative use of the SELECT clause can do what you are looking for.
Can you explain what these impossible calculations are?
EDIT: Nevermind, checking out this webpage reveals that the sqlite_create_function() adapter is all closed up by the Android SQLite wrapper. That's annoying.

Where clause in SQLite not working in android :(

I'm getting an annoying error when trying to query some data in SQLite.
Here is my code:
Cursor cursor= db.query(TABLE_IMAGES, new String[]{"_id"}, "name" +" = "+compareToThis, null, null, null, null);
I'm just returning the cursor as a string.
The error is saying:
no such column: compareToThis: while compiling.....the statement
My question is: why is SQLite setting the compareToThis attribute as a column when it's just a value?
How can I fix this?
Thanks in advance.

Cursor cursor= db.query(TABLE_IMAGES, new String[]{"_id"}, "name" +" = ?", new String[]{compareToThis}, null, null, null);
The selection must include placeholder for parameter, and the next argument should be the array of parameters.

The solution by Vladimir works, however if you are like me and wonder why your approach did not work initially when it should have, here is why:
It is because it expects an integer unless you used (single or double) quotation marks to indicate that it is a string.
For example, in MySql this would return no results:
SELECT * FROM clients WHERE firstName = Bob; -- This will not work.
However when you surround it with quotations, it will return a result because it identifies Bob as a String literal.
Select * FROM clients WHERE firstName = 'Bob'; -- Single quotes work.
Select * FROM clients WHERE firstName = "Bob"; -- Double quotes as well.
Therefore for it to work, you would have to surround your compareToString with single quotes, as Muhhammad mentioned within the comments.
Cursor cursor= db.query(TABLE_IMAGES, new String[]{"_id"}, "name" +'" = "+compareToThis+"'", null, null, null, null);