Question

I’m a SQL newbie having used ORMs most of the time. I am having trouble with aliases in the following query:

command.CommandText = @"
    INSERT INTO permissions (userid, remoteid)
        SELECT userid as uid, :remoteid as rid
        FROM users
        WHERE companyid = :companyid
            AND NOT EXISTS (
                SELECT 1
                FROM permissions
                WHERE userid = uid
                AND remoteid = rid
            )";

command.Parameters.AddWithValue("companyid", companyId);
command.Parameters.AddWithValue("remoteid", resourceId);

When the query executes, I get the following error:

ERROR: 42703: column "uid" does not exist

What am I doing wrong? Are aliases supposed to be used like this and can they be used in an INSERT statement?

Answer 1

how about this:

command.CommandText = @"
    INSERT INTO permissions (userid, remoteid)
        SELECT userid, :remoteid as rid
        FROM users uid
        WHERE companyid = :companyid
            AND NOT EXISTS (
                SELECT 1
                FROM permissions
                WHERE userid = uid.userid
                AND remoteid = rid
            )";

command.Parameters.AddWithValue("companyid", companyId);
command.Parameters.AddWithValue("remoteid", resourceId);