[OT] Idea to get all columns from multiple tables in DB
Jesse Phillips
Jesse.K.Phillips+D at gmail.com
Wed Jan 8 02:28:57 UTC 2020
On Tuesday, 7 January 2020 at 21:01:46 UTC, Steven Schveighoffer
wrote:
> connection.query("SELECT e.*, 'user_' as __prefix, u.* FROM
> ...").byItem!(Equipment, DB.colPrefix!"user_", User)
>
> [...]
>
> Is this a technique that is used by anyone regularly? If so,
> what is it called? I'm very excited about this, because I want
> to minimize DB round trips, and also fetch related items as
> they come in, instead of serializing all of one type to an
> array and then fetching the rest with individual queries, but I
> didn't want to type out a lot of SQL (or generate it based on
> possibly stale struct field names), and have to maintain it any
> time I change something. This solves all the problems in a neat
> way.
>
> -Steve
I don't believe I've seen this pattern.
What I realized after watching your talk is that I've generally
married the structure to the query rather then the tables or data.
Select user.name, equip.product...
struct Ownership {
string usersname;
string product;
}
I this situation the assignment comes from position and not by
column name. You lose the * as you mentioned.
What I have not done is thought about how our application differ
for dealing with the data.
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