I'm taking the SQL programming and procedural logic course on the academy.

One of the lessons concerns EXECUTE IMMEDIATE. It's a bit confusing: the slides use a syntax with (?) as parameter marker, while the video demo uses a syntax with double pipe.

So first question: which of these two syntaxes is the preferred one?

In the lab environment, I tried to use EXECUTE IMMEDIATE to dynamically select a column from a table, passing the name of the column as a parameter. This is the code:

DECLARE OR REPLACE column_name STRING = "o_orderpriority";
DECLARE OR REPLACE sql_string STRING = 
"SELECT (?) FROM orders LIMIT 10";

EXECUTE IMMEDIATE sql_string USING column_name;

The result is a table with a column that contains 10 times the word o_orderpriority.

Second question: is there a way to make EXECUTE IMMEDIATE interpret the parameter value as a column name, and not as a literal string?