Exploit DBI callbacks to make MySQL behave.

Fixed compatibility issues on MySQL. Bricolage now sets `sql_mode` when it
connects to the database, so that MySQL itself does not have to globally set
that option, as it could cause conflicts with other apps running on MySQL.
Also removed the attempt to set C<sql_mode> globally at installation time; it
was bad manners, really.

I used the DBI's callback support to make this work, so bumped up the minimum
required DBI to 1.49. That's five years old already, so everyone should be
fine.

lib/Bric/Admin.pod

@@ -343,7 +343,7 @@ START MODULE LIST
 
 =item Devel::Symdump
 
-=item DBI 1.18
+=item DBI 1.49
 
 =item Error
 

lib/Bric/Changes.pod

@@ -547,6 +547,14 @@ documents with spaces or other URI-escapeable characters in their file names.
 Thanks to Scott Lanning for the spot, and Aaron Fuleki for the kick to get it
 fixed (Bug #82 / #1456). [David]
 
+=item *
+
+Fixed compatibility issues on MySQL. Bricolage now sets C<sql_mode> when it
+connects to the database, so that MySQL itself does not have to globally set
+that option, as it could cause conflicts with other apps running on MySQL.
+Also removed the attempt to set C<sql_mode> globally at installation time; it
+was bad manners, really. Thanks to Waldo Jaquith for the report. [David]
+
 =back
 
 =head1 Version 1.11.1 (2008-10-03)

lib/Bric/Util/DBD/mysql.pm

@@ -51,7 +51,18 @@ use constant DSN_STRING => 'database=' . DB_NAME
   . (DB_PORT ? eval "';port=' . DB_PORT" : '');
 
 # This is to set up driver-specific database handle attributes.
-use constant DBH_ATTR => ( );
+use constant DBH_ATTR => (
+    Callbacks => {
+        connected => sub {
+            my $dbh = shift;
+            $dbh->do(q{
+                SET SESSION sql_mode='ansi,strict_trans_tables,no_auto_value_on_zero';
+            }) unless exists $dbh->{private_bric_sql_mode};
+            $dbh->{private_bric_sql_mode} = 1;
+            return;
+        },
+    },
+);
 
 # This is the maximum for LIMIT rowcount in MySQL
 use constant LIMIT_DEFAULT => '18446744073709551615';

sql/mysql/Bric.sql

@@ -73,5 +73,4 @@ CREATE CAST (integer AS boolean)
   WITH FUNCTION int_to_boolean(integer) AS IMPLICIT;
 */
 
-SET GLOBAL sql_mode='ansi,strict_trans_tables';
 SET SESSION sql_mode='ansi,strict_trans_tables,no_auto_value_on_zero';