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retrieve particular column between different columns of sqlite databse in android

Here is the code, by this I can retrieve all the columns data from the database. But the problem is that now I want to retrieve only one column, that is my requirement.link1st link 2nd link3rd
word_list = new ArrayList<>();
SQLiteDatabase sd = mydb.getWritableDatabase();
Cursor cursor = sd.query("stickerstable",null, null, null, null, null, null);
if (cursor.moveToFirst()){
do{
word_list.add(new data_items(
cursor.getInt(cursor.getColumnIndex(ID)),
cursor.getString(cursor.getColumnIndex(STICKER_AUTHOR)),
cursor.getString(cursor.getColumnIndex(STICKER_NAME)
)));
}while (cursor.moveToNext());
cursor.close();
sd.close();
}

You can use rawQuery instead of query
Cursor cursor = sd.rawQuery("SELECT YOUR_COLUMN FROM stickerstable",null);
replace YOUR_COLUMN with the name of column you want to retrieve you can even use your Constants like this
Cursor cursor = sd.rawQuery("SELECT " + ID + " FROM stickerstable",null);
or a better way to use String.format
Cursor cursor = sd.rawQuery(String.format("SELECT %s FROM stickerstable", ID),null);
UPDATE
you can use query and specify the column in the second argument
Cursor cursor = sd.query("stickerstable",new String[]{ID}, null, null, null, null, null);
when you pass null means get all columns

How to do a rtrim() to a Android Cursor query?

I have the following query:
Cursor c = sd.query(itemsTable.Table_Name, columns, itemsTable.ItemNumber + "= ?", selectionArgs, null, null, null);
I need to be able to do this:
'SQL Query I am running on the database using for testing
select * from items where rtrim(itemnumber) = '292664'
Where itemnumber is my selectionArgs.
The SQL query returns the correct results but the cursor query returns null.
I would rather not change the way I am running queries and would like to know if there is a way to convert my existing query to work the same as the SQL query.

Try the following:
String selection = "RTRIM(" + itemsTable.ItemNumber + ") = ?";
String[] selectionArgs = new String[] {"292664"}; // or whatever
Cursor c = sd.query(itemsTable.Table_Name, columns, selection, selectionArgs, null, null, null);

Android: SQLite Databasing -- ADDING and CURSORS

I'm trying to understand how cursors work and I don't understand a portion of this code --
(lifted off of http://www.vogella.com/articles/AndroidSQLite/article.html)
public Comment createComment(String comment) {
ContentValues values = new ContentValues();
values.put(MySQLiteHelper.COLUMN_COMMENT, comment);
long insertId = database.insert(MySQLiteHelper.TABLE_COMMENTS, null,
values);
Cursor cursor = database.query(MySQLiteHelper.TABLE_COMMENTS,
allColumns, MySQLiteHelper.COLUMN_ID + " = " + insertId, null,
null, null, null);
cursor.moveToFirst();
Comment newComment = cursorToComment(cursor);
cursor.close();
return newComment;
}
Can someone please explain what is going on here?
This is what I THINK is going on - He is inserting values into the table under the column named comment. He then does a query setting the cursor to where he added the comment in the table.
Then I am confused on why he does cursor.moveToFirst(). Isn't the cursor pointing to the current comment he just added? I thought he is trying to return the comment he just inserted into the table, so couldn't he just remove the moveToFirst() method?

Cursor cursor = database.query(MySQLiteHelper.TABLE_COMMENTS,
allColumns, MySQLiteHelper.COLUMN_ID + " = " + insertId, null,
null, null, null);
Returns results are cursor object.
cursor.moveToFirst();
Make sure your are pointing to first element in the cursor object (or) cursor is not empty.
Comment newComment = cursorToComment(cursor);
Calling another method to go through the cursor and perform what ever logic coded inside the method, which return Comment object.
cursor.close();
Close the cursor, so that it would be eligible GC and memeory will be free.
return newComment;
Return the comment object to caller.

From the docs at http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html
query returns: "A Cursor object, which is positioned before the first entry."
Then, http://developer.android.com/reference/android/database/Cursor.html
says moveToFirst() : "Move the cursor to the first row."

Query only the first data from a table

I'm trying to query only the first data from the table.
Cursor img_cursor = db.query(
IMAGE_URL_TABLE_NAME,
new String[]{"small_img_url" , "large_img_url"},
null",
null, null, null, null);
Could somebody tell me how to implement a query where only the first data is retrieved from a table?
Solution
I think I solved the answer:
Cursor img_cursor = db.query(
IMAGE_URL_TABLE_NAME,
new String[]{"small_img_url" , "large_img_url"},
null",
null, null, null, null , "1");
I used limit 1 first, but the application crashed. Only if I pass the number as a String will it work. The query has 8 parameters while we're using the limit parameter.

limit 1
From Documentation:
public Cursor query (boolean distinct, String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit)
so, put your last argument to be "limit 1".
Cursor img_cursor = db.query(
IMAGE_URL_TABLE_NAME,
new String[]{"small_img_url" , "large_img_url"},
null,
null, null, null, "limit 1");

How to perform an SQLite query within an Android application?

I am trying to use this query upon my Android database, but it does not return any data. Am I missing something?
SQLiteDatabase db = mDbHelper.getReadableDatabase();
String select = "Select _id, title, title_raw from search Where(title_raw like " + "'%Smith%'" +
")";
Cursor cursor = db.query(TABLE_NAME, FROM,
select, null, null, null, null);
startManagingCursor(cursor);
return cursor;

This will return you the required cursor
Cursor cursor = db.query(TABLE_NAME, new String[] {"_id", "title", "title_raw"},
"title_raw like " + "'%Smith%'", null, null, null, null);

Alternatively, db.rawQuery(sql, selectionArgs) exists.
Cursor c = db.rawQuery(select, null);

This will also work if the pattern you want to match is a variable.
dbh = new DbHelper(this);
SQLiteDatabase db = dbh.getWritableDatabase();
Cursor c = db.query(
"TableName",
new String[]{"ColumnName"},
"ColumnName LIKE ?",
new String[]{_data+"%"},
null,
null,
null
);
while(c.moveToNext()){
// your calculation goes here
}

I came here for a reminder of how to set up the query but the existing examples were hard to follow. Here is an example with more explanation.
SQLiteDatabase db = helper.getReadableDatabase();
String table = "table2";
String[] columns = {"column1", "column3"};
String selection = "column3 =?";
String[] selectionArgs = {"apple"};
String groupBy = null;
String having = null;
String orderBy = "column3 DESC";
String limit = "10";
Cursor cursor = db.query(table, columns, selection, selectionArgs, groupBy, having, orderBy, limit);
Parameters
table: the name of the table you want to query
columns: the column names that you want returned. Don't return data that you don't need.
selection: the row data that you want returned from the columns (This is the WHERE clause.)
selectionArgs: This is substituted for the ? in the selection String above.
groupBy and having: This groups duplicate data in a column with data having certain conditions. Any unneeded parameters can be set to null.
orderBy: sort the data
limit: limit the number of results to return

Try this, this works for my code
name is a String:
cursor = rdb.query(true, TABLE_PROFILE, new String[] { ID,
REMOTEID, FIRSTNAME, LASTNAME, EMAIL, GENDER, AGE, DOB,
ROLEID, NATIONALID, URL, IMAGEURL },
LASTNAME + " like ?", new String[]{ name+"%" }, null, null, null, null);