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Comparing AnyEvent-DBI/README (file contents):
Revision 1.1 by root, Mon Jun 9 14:28:44 2008 UTC vs.
Revision 1.2 by root, Mon Jul 21 02:34:40 2008 UTC

1NAME 1NAME
2 AnyEvent::DBI - asynchronous DBI access 2 AnyEvent::DBI - asynchronous DBI access
3 3
4SYNOPSIS 4SYNOPSIS
5 use AnyEvent::DBI; 5 use AnyEvent::DBI;
6
7 my $cv = AnyEvent->condvar;
8
9 my $dbh = new AnyEvent::DBI "DBI:SQLite:dbname=test.db", "", "";
10
11 $dbh->exec ("select * from test where num=?", 10, sub {
12 my ($rows, $rv) = @_;
13
14 print "@$_\n"
15 for @$rows;
16
17 $cv->broadcast;
18 });
19
20 # asynchronously do sth. else here
21
22 $cv->wait;
6 23
7DESCRIPTION 24DESCRIPTION
8 This module is an AnyEvent user, you need to make sure that you use and 25 This module is an AnyEvent user, you need to make sure that you use and
9 run a supported event loop. 26 run a supported event loop.
10 27
… …
12 separate "DBI-Server" processes and sending them requests. 29 separate "DBI-Server" processes and sending them requests.
13 30
14 It means that you can run DBI requests in parallel to other tasks. 31 It means that you can run DBI requests in parallel to other tasks.
15 32
16 The overhead for very simple statements ("select 0") is somewhere around 33 The overhead for very simple statements ("select 0") is somewhere around
17 120% to 200% (single/dual core CPU) compared to an explicit 34 120% to 200% (dual/single core CPU) compared to an explicit
18 prepare_cached/execute/fetchrow_arrayref/finish combination. 35 prepare_cached/execute/fetchrow_arrayref/finish combination.
19 36
20 METHODS 37 METHODS
21 $dbh = new AnyEvent::DBI $database, $user, $pass, [key => value]... 38 $dbh = new AnyEvent::DBI $database, $user, $pass, [key => value]...
22 Returns a database handle for the given database. Each database 39 Returns a database handle for the given database. Each database
… …
44 request callback without any arguments. 61 request callback without any arguments.
45 62
46 If omitted, then "die" will be called on any errors, fatal or 63 If omitted, then "die" will be called on any errors, fatal or
47 not. 64 not.
48 65
49 $dbh->exec ("statement", @args, $cb->($rows, %extra)) 66 $dbh->exec ("statement", @args, $cb->($rows, $rv, ...))
50 Executes the given SQL statement with placeholders replaced by 67 Executes the given SQL statement with placeholders replaced by
51 @args. The statement will be prepared and cached on the server side, 68 @args. The statement will be prepared and cached on the server side,
52 so using placeholders is compulsory. 69 so using placeholders is compulsory.
53 70
54 The callback will be called with the result of "fetchall_arrayref" 71 The callback will be called with the result of "fetchall_arrayref"
55 as first argument and possibly a hash reference with additional 72 as first argument (or "undef" if the statement wasn't a select
56 information. 73 statement) and the return value of "execute" as second argument.
74 Additional arguments might get passed as well.
57 75
58 If an error occurs and the "on_error" callback returns, then no 76 If an error occurs and the "on_error" callback returns, then no
59 arguments will be passed and $@ contains the error message. 77 arguments will be passed and $@ contains the error message.
60 78
61SEE ALSO 79SEE ALSO

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