Mysql ruby prob

ruby-talk
1

Hi,

after hours of reading and searching i can't get the solution
code:

require 'mysql'
my = Mysql.new("localhost", "user", "", "database")
data = my.query("select * from books Limit 5")
p "first time"
data.each { |d| p d[0]}
p "again"
data.each { |d| p d[0]}

Result:
"first time"
"7"
"9"
"11"
"12"
"14"
"again"

I expected that the result would be:

"first time"
"7"
"9"
"11"
"12"
"14"
"again"
"7"
"9"
"11"
"12"
"14"

I get this result only if i add

require 'mysql'
my = Mysql.new("localhost", "user", "", "database")
data = my.query("select * from books Limit 5")
p "first time"
data.each { |d| p d[0]}
p "again"
data = my.query("select * from books Limit 5") << ADDED
data.each { |d| p d[0]}

So i think thats not the rigth way - don't repeat yourself

Thanks in advance
DG

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2

after hours of reading and searching i can't get the solution
code:

require 'mysql'

[iterating twice through the same result set, expecting the rows twice]

I get this result only if i add

require 'mysql'
my = Mysql.new("localhost", "user", "", "database")
data = my.query("select * from books Limit 5")
p "first time"
data.each { |d| p d[0]}
p "again"
data = my.query("select * from books Limit 5") << ADDED
data.each { |d| p d[0]}

So i think thats not the rigth way - don't repeat yourself

The result set returned by the query is not an array of rows. It is an
interface to reading the results row by row without storing all of them in
memory at once. This means that as you iterate, it throws out the previous
row. If you want an array of rows, through which you can iterate
as often as you like, use this:

require 'mysql'
my = Mysql.new("localhost", "user", "", "database")
data = my.query("select * from books Limit 5").extend(Enumerable).to_a
# ...

Thanks in advance
DG

--Greg

ยทยทยท

On Tue, Mar 25, 2008 at 12:55:02AM +0900, abc- wrote: