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Can't extract integer from cursor after preforming sqlite query in Android

I'm working on an small android app that maintains a small database of tools which I lend out to other people.
As part of the app, I am incorporating an sqllite database, where I am having a bit of trouble performing queries and working with cursors once the queries have been executed.
The code in question is as follows:
String COLUMN_NAME = "toolName";
String[] columns = { COLUMN_NAME };
String selection = COLUMN_NAME + " =?";
String[] selectionArgs = {tool};
Cursor cursor = mToolDb.query(ToolStatisticContract.ToolStatisticEntry.TABLE_NAME, columns,
selection, selectionArgs, null, null, null, null);
return Integer.parseInt(cursor.getString(3));
The contract for the database is as follows:
public class ToolStatisticContract {
public static final class ToolStatisticEntry implements BaseColumns {
public static final String TABLE_NAME = "tooltable";
public static final String COLUMN_TOOL_NAME = "toolName";
public static final String COLUMN_LIFESPAN = "lifespan";
public static final String COLUMN_USAGE = "usageTime";
}
}
I am essentially trying to extract out the value from COLUMN_USAGE, which seems to be producing errors with regards to parsing the value to an integer. The value in the COLUMN is actually an integer typecasted as a String from a previous segment of code, so I'm fairly certain the error is encompasssed with the code snippets above.
Thanks again in advance for all your help!

The code in question is as follows
The net SQL statement is something like:
SELECT toolName FROM tooltable WHERE toolName = ?
And there is no column with index 3, since you are only returning 1 column.
You need to:
Have usageTime in your column list (COLUMNS)
Move the Cursor to a valid row (as it initially is positioned before the first row)
Pass getInteger() the value that lines up with COLUMNS to retrieve usageTime

You could use the following. This uses null instead of columns, which will get all columns (i.e. resolves to SELECT * FROM table). It checks that a row has been returned and only then does it try to get the data. It also closes the cursor (you should close a cursor when done with it). It uses cursor.getInt() to get the integer value rather than convert it from a string to int. It assumes that you'll only get 1 row (if no rows then 0 will be returned).
int returnvalue = 0;
String COLUMN_NAME = "toolName";
String[] columns = { COLUMN_NAME };
String selection = COLUMN_NAME + " =?";
String[] selectionArgs = {tool};
Cursor cursor = mToolDb.query(ToolStatisticContract.ToolStatisticEntry.TABLE_NAME, null,
selection, selectionArgs, null, null, null, null);
if (cursor.getCount() > 0) {
cursor.moveToFirst();
returnvalue = cursor.getInt(2);
//or returnvalue = Integer.parseInt(cursor.getString(2));
}
cursor.close();
return returnvalue;
Note! I haven't checked this just coded it from memory, so apologies for the odd mistake.
To do the above using specific columns then you could use:-
String COLUMN_NAME = "toolName";
String[] columns = { COLUMN_USAGE };
String selection = COLUMN_NAME + " =?";
String[] selectionArgs = {tool};
Cursor cursor = mToolDb.query(ToolStatisticContract.ToolStatisticEntry.TABLE_NAME, columns,
selection, selectionArgs, null, null, null, null);
In which case the column index would be 0 (that is the index is according to the column's in the cursor). However it might be better to use, the following which gets the column index according to the column's name:-
cursor.getInt(cursor.getColumnIndex(COLUMN_USAGE);

The easiest way to read a single value from the database is to use a helper function that allows you to avoid having to handle cursor objects:
String query = "SELECT usageTime FROM tooltable WHERE toolName = ?";
String[] selectionArgs = { tool };
long returnvalue = DatabaseUtils.longForQuery(mToolDb, query, selectionArgs);

How to filter content resolver query results in android? Passing selection parameter still doesn't work

I'm trying to filer out city names and return matching cities based on the selection parameter being passed.
However the query call still returns all the rows. Even tried putting in a fake city name that doesn't already exist in the database and it still spits out the same original rows.
public void addLocation(String cityName){
Cursor cursor = mContext.getResolver().query(
WeatherContract.LocationEntry.CONTENT_URI,
null,
WeatherContract.LocationEntry.COLUMN_LOCATION_SETTING +
" = " + cityName,
null,
null);
I've read the Android docs over and over, ContentResolver Query, and passing the selection parameter in doesn't seem to be doing anything.
public final Cursor query (Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder)

Assuming the provider you're using is androidx.core.content.FileProvider (according to what you've declared in your manifest), the selection, selectionArgs and sortOrder parameters of FileProvider.query are... ignored in AndroidX's implementation !
See the v1.2.0 source here (line 409)
The only solution I found is to filter and sort the results post-query, in your own code.
And yeah, that's kinda sad...

Instead of passing the value in the selection parameter, put it in selectionArgs.
public void addLocation(String cityName){
String[] args = { cityName };
Cursor cursor = mContext.getResolver().query(
WeatherContract.LocationEntry.CONTENT_URI,
null,
WeatherContract.LocationEntry.COLUMN_LOCATION_SETTING +
" = ?",
args,
null);

Android fails to call SQLite WHERE column LIKE '%?%' The statement has 0 parameters

With this code
public static List<App> findByKeyword(Context context, String keyword){
ContentResolver resolver = context.getContentResolver();
Uri uri = getContentUri();
String[] projection = DataColumns.ALL;
String selection = DataColumns.NAME+" like '%?%' ";
String[] selectionArgs = {keyword};
Cursor cursor = resolver.query(uri, projection, selection, selectionArgs, DEFAULT_ORDER );
return cursorToList(cursor);
}
I get error
Caused by: java.lang.IllegalArgumentException: Cannot bind argument at index 1 because the index is out of range. The statement has 0 parameters.
The SQLite raw query should be SELECT * FROM table WHERE name LIKE '%?%'
but there is problem of using parameter though ContentResolver query API
I also tried using " quotes
String selection = DataColumns.NAME+" like \"%?%\" ";
It also says
The statement has 0 parameters.

Try the other way round:
String selection = DataColumns.NAME+" like ? ";
String[] selectionArgs = new String[]{ "%"+keyword+"%" };
hope it helps

retrieve a single query from a data base in android by sqlite

I'm trying to retrieve a single row from my database using SQLite but for some reason my program crashes. When I search the log I get the next error:
Index -1 is requested with size of 1
I searched the web for solutions but it looks like my code is correct. I can delete a row with that parameter so I know that the position is right. It's probably how I write the query but I just don't know what's wrong with it. Can someone see why I'm doing wrong?
This is the code for the query:
public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + /jokes_table");
final Uri _URI = Uri.parse(MyContentProvider.CONTENT_URI + "/2");
String positions = intent.getStringExtra("position_in_db");
Cursor cur = getBaseContext().getContentResolver().query(_URI, new String[] {"Joke","Author","Date","Status"} , MyContentProvider.ID + " = " + intent.getStringExtra("position_in_db") , null , null );
my query method :
public Cursor query(Uri uri, String[] projection, String selection,
String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder qb = new SQLiteQueryBuilder();
String a;
switch (sUriMatcher.match(uri))
{
case COLLECTION_URI_INDICATOR:
qb.setTables(TABLE_NAME);
qb.setProjectionMap(projectionMap);
break;
case SINGLE_ITEM_URI_INDICATOR:
qb.setTables(TABLE_NAME);
qb.setProjectionMap(projectionMap);
qb.appendWhere(ID);
break;
default:
throw new IllegalArgumentException("Unknown URI " + uri);
}
SQLiteDatabase db = mOpenHelper.getReadableDatabase();
Cursor c = qb.query(db, projection, selection, selectionArgs, null, null, null);
c.setNotificationUri(getContext().getContentResolver(), uri);
return c;
}
When I try to get all the rows by that query it works fine. The only problem is that I can't retrieve specific row. I try to change the selection with ? and try to see the string before I call the query but it won't work. Trying to reach data from the cursor by
cur.getString(getColumnIndex("Joke"));
ends the program. Can someone help me please?

What is your selection and selectionArgs??
you can try this
selection = ROW_ID_COLUMN_NAME + " =? "; // take a note on the "Space" between this statement
selectionArgs = { ROW_ID };
c = qb.query(db, projection, selection, selectionArgs, null, null, null);
// moveToFirst() method may prevent error when accessing 0 row cursor.
if (c.moveToFirst()) {
c.getString(getColumnIndex("Joke"));
}

Group By in ContentResolver in Ice Cream Sandwich

I am making a query on the Android Contacts ContentProvider. I need a Group By clause. In Gingerbread and Honeycomb, I do something like this to search phone numbers and emails at the same time:
(The actual WHERE clause is much more complicated as it includes types checks. This is a simplification, but it yields the same result)
String request = Phone.NUMBER + " LIKE ? OR " + Email.DATA + " LIKE ?";
String[] params = new String["%test%", "%test%"];
Cursor cursor = getContentResolver().query(
Data.CONTENT_URI,
new String[] { Data._ID, Data.RAW_CONTACT_ID },
request + ") GROUP BY (" + Data.RAW_CONTACT_ID,
params, "lower(" + Data.DISPLAY_NAME + ") ASC");
The injection of the ')' finishes the WHERE clause and allow the insertion of a GROUP BY clause.
However, in Ice Cream Sandwich, it appears that the ContentProvider detects this and adds the correct number of parenthesis to prevent my injection. Any other way of doing this in a single cursor query?
Edit
Currently, I have removed the GROUP BY, and added a MatrixCursor to limit the impact, but I'd rather have a real cursor:
MatrixCursor result = new MatrixCursor(new String[] { Data._ID, Data.RAW_CONTACT_ID });
Set<Long> seen = new HashSet<Long>();
while (cursor.moveToNext()) {
long raw = cursor.getLong(1);
if (!seen.contains(raw)) {
seen.add(raw);
result.addRow(new Object[] {cursor.getLong(0), raw});
}
}

I recently battled this issue querying the CallLog.Calls DB (where we were not able to modify the ContentProvider). What we ended up going with was building a query that looked like this:
SELECT _id, date, duration, type, normalized_number FROM calls WHERE _id IN (
SELECT _id FROM calls WHERE date < ? GROUP BY normalized_number ORDER BY date DESC LIMIT ?
);
The idea here is that we place any valid sqlite in our subquery, return a list of ids and then query again for all calls with those ids.
The final code looked something like this:
String whereClause = "_id IN (SELECT _id FROM calls WHERE data < ? GROUP BY normalized_number ORDER BY date DESC LIMIT ?)";
Cursor cursor = context.getContentResolver().query(
CallLog.Calls.CONTENT_URI,
new String[] { "_id", "date", "duration", "normalized_number" },
whereClause,
new String[]{ String.valueOf(amount), String.valueOf(dateFrom) },
null
);
...
In the case that you're querying for contacts, it would look something like this:
String whereClause = "_id IN (SELECT _id FROM contacts WHERE " + Phone.NUMBER + " LIKE ? OR " + Email.DATA + " LIKE ? GROUP BY " + Data.RAW_CONTACT_ID + " ORDER BY lower(" + Data.DISPLAY_NAME + ") ASC)";
String[] params = new String["%test%", "%test%"];
Cursor cursor = getContentResolver().query(
Data.CONTENT_URI,
new String[] { Data._ID, Data.RAW_CONTACT_ID },
whereClause,
params,
null
);
There will be some decrease in performance (since we're essentially querying twice for the same results), but it will surely be a lot faster than querying for all calls and doing the GROUP BY work in java world and also allows you to build up the query with additional clauses.
Hope this helps. We used this on Oreo and it fulfilled our needs.

You could create a custom Uri such that when your UriMatcher in your ContentProvider gets it, you can insert your group by clause and then execute the raw sql directly on the database.

first off all excuse my POOR English!
I'm new to Java/Android, started with 4.2.1 and fight with that too almost 2 days, then i start reading some more details about SQLiteQueryBuilder the query part is pretty much that what u are looking for ;)
it have:
public Cursor query (SQLiteDatabase db, String[] projectionIn, String selection, String[] selectionArgs, String groupBy, String having, String sortOrder)
the query "function" of the Content Provider only gives you:
query(Uri uri, String[] projection, String selection,String[] selectionArgs, String sortOrder)
here u can trick around, i will post you my code snip:
#Override
public Cursor query(Uri uri, String[] projection, String selection,
String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
final SQLiteDatabase db = mOpenHelper.getReadableDatabase();
/* a String is a Object, so it can be null!*/
String groupBy = null;
String having = null;
switch (sUriMatcher.match(uri)) {
...
...
...
case EPISODES_NEXT:
groupBy = "ShowID";
queryBuilder.setTables(EpisodenTable.TableName);
break;
default:
throw new IllegalArgumentException("Unknown URI " + uri);
}
Cursor c = queryBuilder.query(db, projection, selection, selectionArgs,
groupBy, having, sortOrder);
c.setNotificationUri(getContext().getContentResolver(), uri);
return c;
}
thats its!
here the code i use to execute:
Cursor showsc = getContext().getContentResolver().query(
WhatsOnTVProvider.CONTENT_EPISODES_NEXT_URI,
EpisodenTable.allColums_inclCount,
String.valueOf(Calendar.getInstance().getTimeInMillis() / 1000)
+ " < date", null, null);