Speed up admin front page.

* Don't show a categories summary unless asked via a link
* Don't needlessly join in questionnaire/update summaries
* Switch count(distinct()) to a subselect as it turns out
  select count(*) from (select distinct(user_id) from problem) temp;
  is a lot quicker than select count(distinct(user_id)) from problem;

3 files changed, 31 insertions, 23 deletions

diff --git a/perllib/FixMyStreet/DB/ResultSet/Comment.pm b/perllib/FixMyStreet/DB/ResultSet/Comment.pm
index 270501efc..1b6afb819 100644
--- a/perllib/FixMyStreet/DB/ResultSet/Comment.pm
+++ b/perllib/FixMyStreet/DB/ResultSet/Comment.pm
@@ -32,15 +32,16 @@ sub timeline {
 sub summary_count {
     my ( $rs, $body_restriction ) = @_;
 
-    return $rs->to_body($body_restriction)->search(
-        undef,
-        {
-            group_by => ['me.state'],
-            select   => [ 'me.state', { count => 'me.id' } ],
-            as       => [qw/state state_count/],
-            join     => 'problem'
-        }
-    );
+    my $params = {
+        group_by => ['me.state'],
+        select   => [ 'me.state', { count => 'me.id' } ],
+        as       => [qw/state state_count/],
+    };
+    if ($body_restriction) {
+        $rs = $rs->to_body($body_restriction);
+        $params->{join} = 'problem';
+    }
+    return $rs->search(undef, $params);
 }
 
 1;
diff --git a/perllib/FixMyStreet/DB/ResultSet/Problem.pm b/perllib/FixMyStreet/DB/ResultSet/Problem.pm
index 40076d374..e9f5d0f8e 100644
--- a/perllib/FixMyStreet/DB/ResultSet/Problem.pm
+++ b/perllib/FixMyStreet/DB/ResultSet/Problem.pm
@@ -210,7 +210,10 @@ sub unique_users {
     return $rs->search( {
         state => [ FixMyStreet::DB::Result::Problem->visible_states() ],
     }, {
-        select => [ { count => { distinct => 'user_id' } } ],
+        select => [ { distinct => 'user_id' } ],
+        as     => [ 'user_id' ]
+    } )->as_subselect_rs->search( undef, {
+        select => [ { count => 'user_id' } ],
         as     => [ 'count' ]
     } )->first->get_column('count');
 }
diff --git a/perllib/FixMyStreet/DB/ResultSet/Questionnaire.pm b/perllib/FixMyStreet/DB/ResultSet/Questionnaire.pm
index db4b6e23e..bf1c68c49 100644
--- a/perllib/FixMyStreet/DB/ResultSet/Questionnaire.pm
+++ b/perllib/FixMyStreet/DB/ResultSet/Questionnaire.pm
@@ -113,6 +113,13 @@ sub send_questionnaires_period {
 sub timeline {
     my ( $rs, $restriction ) = @_;
 
+    my $attrs;
+    if (%$restriction) {
+        $attrs = {
+            -select => [qw/me.*/],
+            prefetch => [qw/problem/],
+        }
+    }
     return $rs->search(
         {
             -or => {
@@ -121,24 +128,21 @@ sub timeline {
             },
             %{ $restriction },
         },
-        {
-            -select => [qw/me.*/],
-            prefetch => [qw/problem/],
-        }
+        $attrs
     );
 }
 
 sub summary_count {
     my ( $rs, $restriction ) = @_;
 
-    return $rs->search(
-        $restriction,
-        {
-            group_by => [ \'whenanswered is not null' ],
-            select   => [ \'(whenanswered is not null)', { count => 'me.id' } ],
-            as       => [qw/answered questionnaire_count/],
-            join     => 'problem'
-        }
-    );
+    my $params = {
+        group_by => [ \'whenanswered is not null' ],
+        select => [ \'(whenanswered is not null)', { count => 'me.id' } ],
+        as => [qw/answered questionnaire_count/],
+    };
+    if (%$restriction) {
+        $params->{join} = 'problem';
+    }
+    return $rs->search($restriction, $params);
 }
 1;