From 126b5e6dc4beb29e3e757fab713c618a329b1249 Mon Sep 17 00:00:00 2001
From: Kenichi Ishigaki <ishigaki@cpan.org>
Date: Thu, 11 Feb 2010 03:24:36 +0000
Subject: [PATCH] added placeholder explanation and its test

---
 lib/DBD/SQLite.pm   | 11 +++++++++++
 t/41_placeholders.t | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 t/41_placeholders.t

diff --git a/lib/DBD/SQLite.pm b/lib/DBD/SQLite.pm
index dec0c41..2dd332c 100644
--- a/lib/DBD/SQLite.pm
+++ b/lib/DBD/SQLite.pm
@@ -748,6 +748,17 @@ This is somewhat weird, but works anyway.
 
 =back
 
+=head2 Placeholders
+
+SQLite supports several placeholder expressions, including C<?> and C<:AAAA>. Consult the L<DBI> and sqlite documentation for details. 
+
+L<http://www.sqlite.org/lang_expr.html#varparam>
+
+Note that a question mark actually means a next unused (numbered) placeholder. You're advised not to use it with other (numbered or named) placeholders to avoid confusion.
+
+  my $sth = $dbh->prepare('update TABLE set a=?1 where b=?2 and a IS NOT ?1');
+  $sth->execute(1, 2); 
+
 =head2 Foreign Keys
 
 B<BE PREPARED! WOLVES APPROACH!!>
diff --git a/t/41_placeholders.t b/t/41_placeholders.t
new file mode 100644
index 0000000..a9a5116
--- /dev/null
+++ b/t/41_placeholders.t
@@ -0,0 +1,34 @@
+#!/usr/bin/perl
+
+use strict;
+BEGIN {
+	$|  = 1;
+	$^W = 1;
+}
+
+use t::lib::Test qw/connect_ok/;
+use Test::More;
+use Test::NoWarnings;
+
+plan tests => 9;
+
+my $dbh = connect_ok( RaiseError => 1 );
+ok $dbh->do('create table foo (id integer, value integer)');
+
+ok $dbh->do('insert into foo values(?, ?)',   undef, 1, 2);
+ok $dbh->do('insert into foo values(?1, ?2)', undef, 2, 3);
+ok $dbh->do('insert into foo values(:1, :2)', undef, 3, 4);
+ok $dbh->do('insert into foo values(@1, @2)', undef, 4, 4);
+
+ok $dbh->do(
+	'update foo set id = $1 where value = $2 and id is not $1',
+	undef, 3, 4
+);
+
+my ($count) = $dbh->selectrow_array(
+	'select count(id) from foo where id = ? and value = ?',
+	undef, 3, 4
+);
+
+ok $count == 2;
+