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select distinct value in android sqlite

I try to run the following raw query in android, it seems not work

String query ="SELECT DISTINCT category FROM event";
Cursor  cursor = mDb.rawQuery(query, null);
if (cursor != null) {
     cursor.moveToFirst();
}
return cursor; 

so I decide to use the query() method in android which are something like

Cursor mCursor = mDb.query(EVENT_TABLE, new String[] {KEY_ROWID, KEY_CAT}, null, null,null,null, null)

Can anyone show me how to select the distinct category for using query() instead of rawquery please, any help will be greatly appreciated!

question from:https://stackoverflow.com/questions/11219361/select-distinct-value-in-android-sqlite

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1 Answer

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by (71.8m points)

You can use this method:

public Cursor query (boolean distinct, String table, 
                     String[] columns, String selection, 
                     String[] selectionArgs, String groupBy, 
                     String having, String orderBy, String limit)

Here first argument specifies whether to use distinct or not.


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