Batch Delete items with Content Provider in Android

Question

I\'m trying to batch delete some items in a table.

    String ids = { \"1\", \"2\", \"3\" };

    mContentResolver.delete(uri, MyTables._ID + \"=?\", ids);
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Answer 1

The error occurs because you have a single placeholder (?) in your where clause, while you pass three arguments. You should do:

String ids = { "1", "2", "3" };

mContentResolver.delete(uri, MyTables._ID + "=? OR " + MyTables._ID + "=? OR " + MyTables._ID + "=?", ids);

I do not know if SQLite supports the IN clause, if so you could also do:

String ids = { "1, 2, 3" };

mContentResolver.delete(uri, MyTables._ID + " IN (?)", ids);

Answer 2

You can use ContentProviderOperation for batch deletion/insertion/update in one transaction. It's much nicer you don't have to concatenate strings. It also should be very efficient. For deletion:

    ArrayList<ContentProviderOperation> operations = new ArrayList<ContentProviderOperation>();
    ContentProviderOperation operation;

    for (Item item : items) {

        operation = ContentProviderOperation
                .newDelete(ItemsColumns.CONTENT_URI)
                .withSelection(ItemsColumns.UID + " = ?", new String[]{item.getUid()})
                .build();

        operations.add(operation);
    }

    try {
        contentResolver.applyBatch(Contract.AUTHORITY, operations);
    } catch (RemoteException e) {

    } catch (OperationApplicationException e) {

    }

Answer 3

String sqlCommand = String.format("DELETE FROM %s WHERE %s IN (%s);", TABLE_NAME, KEY_ID, 1,2,3);

db.execSQL(sqlCommand);