MYSQL. Extract data with column filtered - mysql

Question

I got a table like this:
mysql> select * from users;
+--------+----------+------------+-----------+
| userid | username | password | privilege |
+--------+----------+------------+-----------+
| 1 | user1 | password | 1 |
| 2 | david | goodboy | 1 |
| 3 | admin | mastermold | 5 |
| 4 | user4 | password4 | 1 |
| 5 | user5 | password5 | 2 |
| 6 | user6 | password6 | 1 |
| 7 | user7 | password7 | 1 |
+--------+----------+------------+-----------+
7 rows in set
Now, how to extract password of username who is called "david" by the only select query without "password" stored in it and result is in one field. (Don't accept "select * from users")?

Answer 1

Try
select password from users where username='david';

Answer 2

without using mentioning "password"?
well you could grab the column name into a variable and use that like this sqlFiddle
SET #columnName = (SELECT COLUMN_NAME FROM
INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'users'
AND ORDINAL_POSITION = 3);
SET #sql = CONCAT("SELECT ",#columnName," FROM users WHERE username = 'david'");
prepare statement FROM #sql;
execute statement;

Answer 3

Well, you mean that your query result shouldn't have the string "password", if I have got it correctly. Even though I am posting the answer, You should really consider #MarcB comment and try learning SQL first.
Your query should go like this
select `password` from users where username='david'
and lower(`password`) not like '%password%';