mysql替换变量

Question

I don't really want to open a new question for such a basic question but I need help. Im studying mysql and just started with substitution variables

Consider this simple statement:

  SELECT empid, surname 
    from employees
    where
    empid = &empid

Oracle gives me the error not all variables bound. Please, could someone enlighten me as to what is wrong with my statement?

Answer 1

See the Oracle Application Express docs: https://docs.oracle.com/cd/E14373_01/user.32/e13370/sql_proc.htm#AEUTL228

Bind variables are prefixed with a colon.

So change your query to:

 SELECT empid, surname 
    from employees
    where
    empid = :empid

When you run the query, you will get a popup window asking you to supply the value of :empid.