Why SELECT * is bad for SQL performance (2020)

Re:Why SELECT * is bad for SQL performance (2020) by evanelias on Monday February 15, 2021 @10:38AM (#26143690)

That's fair, but some database systems have added functionality to avoid this specific problem. In Oracle, MySQL, and MariaDB, you can mark a column as INVISIBLE to exclude it from SELECT *.

It's still not a great practice to use SELECT *, but at least this gives you a way to add columns without breaking existing applications. It's also useful when you plan to remove a column, to test in advance whether anything using SELECT * would break without that column there.

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Re:Why SELECT * is bad for SQL performance (2020) by bhandziuk on Monday February 15, 2021 @02:21PM (#26146121)

That's an interesting feature and could be helpful for varbinary(max) type columns. But also very annoying because I'd be thinking "Does that column exist or not? Why is it not showing up for me?"

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