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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

SqlLite Select where date and order by time

I have this problem, I am trying to select by date and i also need to order by time in descending order. I am not sure if I am doing this right, because the application crashes after adding the code below. Please tell me if this query is correct?
public Cursor getAllDataDelete(){
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor
cursor = db.query(TABLE_NAME, new String[] {ID, TITLE,
DESCRIPTION, DATE, TIME}, null, null, null, null, TIME + " ASC");
return cursor;

How do you iterate over a cursor in reverse order

Usually when I iterate over a cursor I use something like the following:
while (cursor.moveToNext()) {
// get stuff from the cursor
}
What's the best way to iterate an Android Cursor? has a nice discussion of the various options. But now I need to go backwards from last to first over the cursor.
So what can I do?

There are at least two options.
First, to specifically answer your question about iterating backwards over the cursor, you could do the following:
for (cursor.moveToLast(); !cursor.isBeforeFirst(); cursor.moveToPrevious()) {
// get stuff from the cursor
}
Second, you could populate the cursor in reverse order from sql and then iterate over the cursor in your normal way:
SQLiteDatabase db = myHelper.getWritableDatabase();
String[] columns = { MyDatabaseHelper.TEST_DATE, MyDatabaseHelper.SCORE };
String orderBy = MyDatabaseHelper.TEST_DATE + " DESC"; // This line reverses the order
Cursor cursor = db.query(MyDatabaseHelper.TESTS_TABLE_NAME, columns,
null, null, null, null, orderBy, null);
while (cursor.moveToNext()) {
// get stuff from the cursor
}
cursor.close();
db.close();

You can start the cursor in the last position, and use moveToPrevious() until you've finished.
cursor.moveToLast();
do
{
// Stuff
}
while (cursor.moveToPrevious());

Android SQLiteDatabase: Reading one column

I have a one row database just for saving app data. My goal is to read one column (one value) from it.
This query returns all the columns in a Cursor:
public Cursor readAll() {
return getReadableDatabase().query(tableName, null, null, null, null, null, null);
}
It returns a Cursor with one row in it, just perfect. However, I don't want to read all columns at once, because it's slow as I have blob's in db too.
Instead, I'd like to read just one column at a time, separately. For example, for a column called "TEXT" it would be this:
public Cursor readText() {
String[] projection = new String[]{"TEXT"};
return getReadableDatabase().query(tableName, projection, null, null, null, null, null);
}
However, this won't work, as I get back a Cursor with zero rows.
So, how to read a specific column from SQLiteBatabase in Android?

public Cursor readText() {
return getReadableDatabase().rawQuery("SELECT colName FROM myTable", new String[] {});
}

Syntax seems to be correct. Check please that you use right name of the column. Showing the table generation code and actual query code could help.

You can use this one also
public Cursor readText() {
return getReadableDatabase().rawQuery("SELECT column_name FROM table_name", null);
}

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");