Find by sql

[davidw]

This fixes https://github.com/ChicagoBoss/boss_db/issues/175 by creating a find_by_sql.

It's likely that we should change the form some to accommodate non-sql using databases.

[rambocoder]

+1 changing rebar.conf dep to epgsql/epgsql :)

[davidw]

Further thoughts on this?

[choptastic]

This seems like a good idea to me still. I'd like to look to adding it to at least the MySQL adapter as well.

I can do that.

-Jesse

On Mon, May 12, 2014 at 9:56 AM, David N. Welton notifications@github.comwrote:

Further thoughts on this?

— Reply to this email directly or view it on GitHubhttps://github.com/ChicagoBoss/boss_db/pull/176#issuecomment-42842224 .

Jesse Gumm Owner, Sigma Star Systems 414.940.4866 || sigma-star.com || @jessegumm

[choptastic]

I have this merged into my local branch, and I'm working on the mysql version. One thing, so that I ensure that the adjustment is done correctly, it appears from the epgsql readme that the replacement is done like:

boss_db:find_by_sql(person, "Select * from person where a=$1 and b=$2", [A, B]).

The way I've currently done the mysql version is it will crash if $3 is referenced but the provided parameter list only has 2 elements, but is perfectly acceptable to have unreferenced parameters.

So:

This will crash (because there is no 2nd parameter). boss_db:find_by_sql(person, "Select * from person where a=$1 and b=$2", [A]).

And this will be accepted, even though B is never referenced: boss_db:find_by_sql(person, "Select * from person where a=$1 and b=$3", [A, B, C]).

Is this correct?

[davidw]

With Postgres, ultimately it gets turned into:

        Res = pgsql:equery(Conn, Sql, Parameters),

So I think that it's going to be somewhat database specific.

I'm still not 100% convinced about the name, perhaps it'd be nice to give it another one that's less SQL specific, for all the people using other stuff. Nothing comes to mind though.

[choptastic]

What I was asking was if I have the replacement method down. Like params must be $1, $2, $3, and correspond to the specific elements in Parameters? Parameters isn't like a proplist, right? It's just a list, and the params in the SQL can't be named like $name or $id or whatnot, correct?

I want to make sure the syntax is still exchangeable between MySQL and Postgre.

Frankly, I think "find_by_sql" is fine, since it's not pertinent to non-SQL databases, so I wouldn't sweat it for now.

-Jesse

On Fri, May 16, 2014 at 4:45 AM, David N. Welton notifications@github.comwrote:

With Postgres, ultimately it gets turned into:

    Res = pgsql:equery(Conn, Sql, Parameters),

So I think that it's going to be somewhat database specific.

I'm still not 100% convinced about the name, perhaps it'd be nice to give it another one that's less SQL specific, for all the people using other stuff. Nothing comes to mind though.

— Reply to this email directly or view it on GitHubhttps://github.com/ChicagoBoss/boss_db/pull/176#issuecomment-43314592 .

Jesse Gumm Owner, Sigma Star Systems 414.940.4866 || sigma-star.com || @jessegumm

[davidw]

On Postgres, it's like that, yeah. It's just a list, not a proplist. I have no idea if they can have names; I just use the numbers.