From: Mike Baas <mike@initselftech.com>
Date: Fri, 29 Oct 2010 02:55:49 +0000 (-0500)
Subject: Add notes about handling of inflated objects in resultset conditions
X-Git-Tag: v0.08125~58
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits%2FDBIx-Class.git;a=commitdiff_plain;h=0ac0af6c62637a5fdb06ecfb8ba4b60f93bf9d75

Add notes about handling of inflated objects in resultset conditions
---

diff --git a/lib/DBIx/Class.pm b/lib/DBIx/Class.pm
index b32efe4..3b71596 100644
--- a/lib/DBIx/Class.pm
+++ b/lib/DBIx/Class.pm
@@ -295,6 +295,8 @@ hobbs: Andrew Rodland <arodland@cpan.org>
 
 ilmari: Dagfinn Ilmari MannsE<aring>ker <ilmari@ilmari.org>
 
+initself: Mike Baas <mike@initselftech.com>
+
 jasonmay: Jason May <jason.a.may@gmail.com>
 
 jesper: Jesper Krogh
diff --git a/lib/DBIx/Class/Manual/Cookbook.pod b/lib/DBIx/Class/Manual/Cookbook.pod
index 3c08004..6bbd343 100644
--- a/lib/DBIx/Class/Manual/Cookbook.pod
+++ b/lib/DBIx/Class/Manual/Cookbook.pod
@@ -1731,8 +1731,41 @@ See L<SQL::Abstract/array_datatypes> and L<SQL::Abstract/Literal SQL with
 placeholders and bind values (subqueries)> for more explanation. Note that
 L<DBIx::Class> sets L<SQL::Abstract/bindtype> to C<columns>, so you must pass
 the bind values (the C<[1, 2, 3]> arrayref in the above example) wrapped in
-arrayrefs together with the column name, like this: C<< [column_name => value]
->>.
+arrayrefs together with the column name, like this:
+C<< [column_name => value] >>.
+
+=head2 Formatting DateTime objects in queries
+
+To ensure C<WHERE> conditions containing L<DateTime> arguments are properly
+formatted to be understood by your RDBMS, you must use the C<DateTime>
+formatter returned by L<DBIx::Class::Storage::DBI/datetime_parser> to format
+any L<DateTime> objects you pass to L<search|DBIx::Class::ResultSet/search>
+conditions. Any L<Storage|DBIx::Class::Storage> object attached to your
+L<Schema|DBIx::Class::Schema> provides a correct C<DateTime> formatter, so
+all you have to do is:
+
+  my $dtf = $schema->storage->datetime_parser;
+  my $rs = $schema->resultset('users')->search(
+    {
+      signup_date => {
+        -between => [
+          $dtf->format_datetime($dt_start),
+          $dtf->format_datetime($dt_end),
+        ],
+      }
+    },
+  );
+
+Without doing this the query will contain the simple stringification of the
+C<DateTime> object, which almost never matches the RDBMS expectations.
+
+This kludge is necessary only for conditions passed to
+L<DBIx::Class::ResultSet/search>, whereas
+L<create|DBIx::Class::ResultSet/create>,
+L<find|DBIx::Class::ResultSet/find>,
+L<DBIx::Class::Row/update> (but not L<DBIx::Class::ResultSet/update>) are all
+L<DBIx::Class::InflateColumn>-aware and will do the right thing when supplied
+an inflated C<DateTime> object.
 
 =head2 Using Unicode
 
diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm
index 46ac2d1..36647ed 100644
--- a/lib/DBIx/Class/ResultSet.pm
+++ b/lib/DBIx/Class/ResultSet.pm
@@ -245,6 +245,16 @@ documentation for the first argument, see L<SQL::Abstract>.
 
 For more help on using joins with search, see L<DBIx::Class::Manual::Joining>.
 
+=head3 CAVEAT
+
+Note that L</search> does not process/deflate any of the values passed in the
+L<SQL::Abstract>-compatible search condition structure. This is unlike other
+condition-bound methods L</new>, L</create> and L</find>. The user must ensure
+manually that any value passed to this method will stringify to something the
+RDBMS knows how to deal with. A notable example is the handling of L<DateTime>
+objects, for more info see:
+L<DBIx::Class::Manual::Cookbook/Formatting_DateTime_objects_in_queries>.
+
 =cut
 
 sub search {
@@ -1511,6 +1521,15 @@ The return value is a pass through of what the underlying
 storage backend returned, and may vary. See L<DBI/execute> for the most
 common case.
 
+=head3 CAVEAT
+
+Note that L</update> does not process/deflate any of the values passed in.
+This is unlike the corresponding L<DBIx::Class::Row/update>. The user must
+ensure manually that any value passed to this method will stringify to
+something the RDBMS knows how to deal with. A notable example is the
+handling of L<DateTime> objects, for more info see:
+L<DBIx::Class::Manual::Cookbook/Formatting_DateTime_objects_in_queries>.
+
 =cut
 
 sub update {