[__jem]

you're getting downvoted because it's not really a preference, it's pretty widely known to be bad practice and unhygienic in production queries. select * would get your pr rejected and chewed out by dba at every place i've ever worked at. so you kinda just look like you don't know what you're talking about.

[croes]

In an exists query select * is harmless, select 1 and select * result in the same execution plan at least in MS SQL.

In a query than returns result rows it could break the query as soon as you add columns with names that already exist in other tables you joined in the query.

[__jem]

yes, it's harmless in this position but it provides no additional benefits to the select 1 idiom and is suggestive of poor query discipline. it's far easier to say just don't ever use select * in queries.