for loop in lua how to index with array

Question

how can i put my looped value to an array if i have this code?

local data = {
 for row in db:nrows("SELECT song.id, song.title as title, artist.name as name FROM song, artist where song.artist_id = artist.id") do
    {
     song = row.title,
     artist = row.name
    }
  end
}

but i got this error:

unexpected symbol near 'for'

i just wanted to be look like this...

local data = {
 { 
   song = "HI",
   artist = "Tom"
 }
 {
   song = "Hello",
   artist = "mike"
 }
...
}

can anyone can help me about my situation or give some advice about it? thanks in advance

Linus Thiel · Accepted Answer · 2012-05-11 08:46:37Z

3

You would have to do something like this, I think:

result = db:nrows("SELECT song.id, song.title as title, artist.name as name FROM song, artist where song.artist_id = artist.id")

data = {}
for i, row in ipairs(result) do
  data[i] = {}
  data[i].song = row.title
  data[i].artist = row.name
end

Edit: A question though: Why don't you just specify that in the SQL query and use the results as is? I.e.:

data = db:nrows("SELECT song.id, song.title as song, artist.name as artist FROM song, artist where song.artist_id = artist.id")

answered May 11, 2012 at 8:46

Linus Thiel

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1 Comment

gadss Over a year ago

thanks Linus for your answer... about your question, i just want an array for the tableView.lua for my corona sdk..

Jane T · Accepted Answer · 2012-05-11 08:53:07Z

2

Having looked at the documentation dbn:rows iterates the rows and returns a table. So the {} are what are causing the problem.

local data = {}

for row in db:nrows("SELECT song.id, song.title as song, artist.name as artist FROM song, artist where song.artist_id = artist.id") do
  table.insert(data,row)
end

I have not been able to test the above as I don't have Coruna, and use a different lua system.

Reference: http://lua.sqlite.org/index.cgi/doc/tip/doc/lsqlite3.wiki#db_nrows

answered May 11, 2012 at 8:53

Jane T

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