Re: Pass vars value not reference to table.insert

[Jan Schütze <JanS@...>]

This is the source I use.

It uses a luasql mysql connection in mysql.con.

   function mysql_query(query,connection)
       if (connection==nil) then connection=mysql.con end
       return connection:execute(query)
   end
  
   function mysql_get(query,connection)
       local rows={}
       local cur = assert (mysql_query(query,connection))
       local row = cur:fetch ({}, "a")
       while (row) do
           local row2={}
           for key,value in pairs(row)  do
               row2[key]=value
           end
           table.insert(rows,row2)
           row = cur:fetch (row, "a")
       end
       return rows
   end

Since there are 3 elements in the database, (which are correctly printed 
if I add a print_r(row) right after the while beginning.

But if I replace
       while (row) do
           local row2={}
           for key,value in pairs(row)  do
               row2[key]=value
           end
           table.insert(rows,row2)
           row = cur:fetch (row, "a")
       end

with:
       while (row) do
           table.insert(rows,row)
           row = cur:fetch (row, "a")
       end

it won't work and raises errors like I described before.

Kind regards,
 Jan (DracoBlue)

David Given schrieb:
> -----BEGIN PGP SIGNED MESSAGE-----
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>
> Jan Schütze wrote:
> [...]
>   
> > The following pseudo code won't add every 3 rows to the table rows,
> > because row is a variable so rows would contain one item, and 3 pointers
> > to it.
> >             rows={}
> >        local row = fetchRow()
> >        while (row) do
> >            table.insert(rows,row)
> >            row = fetchRow()
> >        end
> >     
>
> The only way you'd end up with the same item three times is if fetchRow()
> were somehow returning the same item every time. It's not reusing the same
> table to return each item, is it --- can we see the implementation?
>
> - --
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