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Tomas Guisasola Gorham wrote:
-- Untested code
-- You'll have to declare next, unpack and table as locals to
-- provide access to them
function select (self, columns, tabname, cond, extra, mode)
local stmt = sql.select (columns, tabname, cond, extra)
local cur = assertexec (self, stmt)
return function ()
-- This table must be created inside this function or it could
-- make `selectall' to return the same row every time.
local t
if mode then t = {} end
--return cur:fetch (t, mode)
local results = { cur:fetch (t, mode) }
if next(results) == nil then -- no more rows
cur:close()
return nil
else
return unpack (results, 1, table.maxn(results))
end
end
end 

...

-- Untested code
function select (self, columns, tabname, cond, extra, mode)
    local stmt = sql.select (columns, tabname, cond, extra)
    local cur = assertexec (self, stmt)
    return function ()
        -- This table must be created inside this function or it could
        -- make `selectall' to return the same row every time.
        local t
        if mode then t = {} end
        return cur:fetch (t, mode)
    end, cur
end

...

local iter, cur = db:select ("*", "table", nil, nil, "a")
for row in iter do
...
end
cur:close()

     Regards,
         Tomás


Both work well.

Second one looks prettier, and runs faster, but the first on is cleaner, since it cleans up after itself. I don't mind the hit in speed, because I am just doing data migration scripts.

Thanks very much for your help

Mike