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Re:Marriott CEO shares post-mortem on last year's hack by ceejayoz on Tuesday March 12, 2019 @01:01PM (#19370352)
> How often do you design a database query to get the count of all rows from a table?

Any time I paginate a list, so it can show the "x of y pages"?

Re:Marriott CEO shares post-mortem on last year's hack by bradjohnson on Tuesday March 12, 2019 @02:24PM (#19371344)
Doesn't make sense to query the db for a count of the number of records that are returned. You can figure that out from the result set inside your application.
Re:Marriott CEO shares post-mortem on last year's hack by ceejayoz on Tuesday March 12, 2019 @02:27PM (#19371375)
If the result set is "all users", you probably don't want to pull tens or hundreds of millions of records just to count them up if you're showing 100 per page.
Re:Marriott CEO shares post-mortem on last year's hack by bradjohnson on Tuesday March 12, 2019 @02:42PM (#19371556)
I think that something like a query for hundreds of millions of records that also required pagination for the exact number of records returned is anomalous and not something that their application would do.
Re:Marriott CEO shares post-mortem on last year's hack by omouse on Tuesday March 12, 2019 @01:03PM (#19370374)
You aren't keeping the count somewhere else, in a cache, let's say?
Re:Marriott CEO shares post-mortem on last year's hack by ceejayoz on Tuesday March 12, 2019 @01:28PM (#19370678)
Sure, but even if you're caching, you're presumably populating that "how many users do we have" widget's cache at least once a day or so.
Re:Marriott CEO shares post-mortem on last year's hack by ars on Tuesday March 12, 2019 @02:16PM (#19371263)
Specifically in this case, there's no reason to show a list of all of the users in the system. What would you do with a list with millions of rows?

A search makes more sense here.

Re:Marriott CEO shares post-mortem on last year's hack by ceejayoz on Tuesday March 12, 2019 @02:22PM (#19371326)
> What would you do with a list with millions of rows?

Not much, but that doesn't mean folks won't.

https://stackoverflow.com/questions says "17,335,212 questions " and the pagination goes "1 2 3 4 5 … 346705", if you want a real-world example.