what is the use of ? in select distinct query

Question

I was going through the code, I found one query where "?"mentioned. query is

select distinct from A inner join B ON A.c =B.a and A.x=B.f and A.x=?

here what is the meaning of A.x=? , not able to understand. is it something with runtime value, if yes then how ? will take runtime parameter.

Parameter marker, i.e. a value provided passed at execution/open. — jarlh, Feb 01 '19 at 14:56
Possible duplicate of [What is parameterized query?](https://stackoverflow.com/questions/4712037/what-is-parameterized-query) — Iłya Bursov, Feb 01 '19 at 14:57

score 0 · Answer 1 · answered Feb 01 '19 at 15:21

0

I'm guessing this is from SSIS.

When you use a parameterised query over anything but ADO.NET, the parameters are defined with question marks. The first question mark is parameter 1, the second is parameter 2 etc. The problem with this is that each parameter can only be used once.

With ADO.NET you can specify parameter names which (in my view) is much better.

answered Feb 01 '19 at 15:21

iainc

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but how I will come to know which is the parameter getting passed to it and from where? is there any good example I am confused with the"?" character here,, – pankaj malvi Feb 04 '19 at 16:29

what is the use of ? in select distinct query

1 Answers1