sql - Android Cursor not returning anything when using a UUID in my where clause -

i'm trying select rows sqllight table in android. here code cursor.

cursor c = db.query(database_table_product_types, new string[] { key_rowid, key_name, key_code, key_groupid }, key_groupid + "=?", new string[] { group }, null, null, null); 

i have tried way:

cursor c = db.query(database_table_product_types, new string[] { key_rowid, key_name, key_code, key_groupid }, key_groupid + "='" + group + "'", null, null, null, null); 

the problem having cursor empty every time run these queries.

if run without clause works fine , returns of rows in table. can run query clause on column no problem, example:

cursor c = db.query(database_table_product_types, new string[] { key_rowid, key_name, key_code, key_groupid }, key_code + "=?", new string[] { "tpeo128" }, null, null, null); 

let me know if there other information me post.

you correct open database read or write? exception don't exists?

if no exception, may try write group string before execute query.

log.d("string where", group); 

maybe string isn't in column key_groupid?