[MUDLET] Databases

Klendathu

I've decided to learn how to use databases for Mudlet, so am starting with a relatively simple idea, a way to store shrine locations. I've created the database (I can see the relevant file in my profile folder), but am encountering an error when I try to db:fetch...

kln		= kln or {}
kln.db		= kln.db or {}

db:create("klndb", {shrines={"divine","roomNum"}}) -- database is created

local klndb = db:get_database("klndb")             -- assign database to variable name

kln.db.testAdd = function()
	db:add(klndb.shrines,{divine="test",roomNum=1234})
end

kln.db.testShow = function()
	display(db.fetch(klndb.shrines))
end

I don't get an error when running kln.db.testAdd() but when I try to run kln.db.testShow(), it returns the following error:

<mudlet-lua/lua/DB.lua:848: attempt to index local 'sheet' (a nil value)>

It returns the same error whether or not I'm using display(). I'm sure I've missed something trivial, but I'm falling at the first hurdle!

Keneanung

You should be using "db:fetch" (with a colon).

Klendathu

Knew it would be something simple that I just couldn't see, thanks!

Klendathu

New question, and I have trawled Google and the Mudlet forums but not found an answer...

Can a database be created in a different folder than the profile folder? If so, how? I've tried adding the path in the db:create line to no avail.

Jacero

@Klendathu There's no way other than editing the db:create function to specify the destination path.

Excerpt from that function:

...
    db.__conn[db_name] = db.__env:connect(getMudletHomeDir() .. "/Database_" .. db_name .. ".db")
...

Keneanung

You could technically temporarily overwrite getMudletHomeDir() to return any path you'd like just for the duration of db:create

Klendathu

Having had a bit of a rummage through the DB.lua file, I'd need to adapt quite a few scripts to be able to create and use a database outside of the profile folder. Seems like more effort than it's worth... for now.

Thanks both, back to my musings