From: Matt S Trout <mst@shadowcat.co.uk>
Date: Thu, 11 Oct 2012 12:45:05 +0000 (+0100)
Subject: demonstrate limit dialects
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=a609e537d08fbb3707dd02adf0df21cae43edcc6;p=dbsrgits%2FData-Query.git

demonstrate limit dialects
---

diff --git a/t/example.t b/t/example.t
index f7999d6..4ccc2a6 100644
--- a/t/example.t
+++ b/t/example.t
@@ -4,65 +4,102 @@ use Data::Query::Renderer::SQL::Naive;
 use Moo::Role ();
 use Devel::Dwarn;
 
-my $renderer = Data::Query::Renderer::SQL::Naive->new;
+sub make_renderer {
+  my $class = do {
+    if ($_[0]) {
+      Moo::Role->create_class_with_roles(
+        'Data::Query::Renderer::SQL::Naive',
+        "Data::Query::Renderer::SQL::Slice::$_[0]"
+      )
+    } else {
+      'Data::Query::Renderer::SQL::Naive'
+    }
+  };
+  $class->new;
+}
+
+my $renderer = make_renderer;
 
-sub render_expr {
+sub to_sql {
   my ($sql, @bindp) = @{$renderer->render($_[0])};
   ($sql, map $_->{value}, @bindp);
 }
 
-DwarnL render_expr(SELECT { $_->foo, "bar" });
-DwarnL render_expr(SELECT { $_->foo, "bar" } FROM { $_->baz });
-DwarnL render_expr(SELECT { $_->foo } FROM { $_->baz, AS('quux') });
-DwarnL render_expr(
+DwarnL to_sql(SELECT { $_->foo, "bar" });
+DwarnL to_sql(SELECT { $_->foo, "bar" } FROM { $_->baz });
+DwarnL to_sql(SELECT { $_->foo } FROM { $_->baz, AS('quux') });
+DwarnL to_sql(
   SELECT { $_->cd->name } FROM { $_->cds, AS('cd') } JOIN { $_->artists }
 );
-DwarnL render_expr(
+DwarnL to_sql(
   SELECT { $_->cd->name }
   FROM { $_->cds, AS 'cd' }
   JOIN { $_->artists, AS 'artist' }
     ON { $_->cd->artistid eq $_->artist->id }
 );
-DwarnL render_expr(
+DwarnL to_sql(
   SELECT { $_->artist->name }
   FROM { $_->artists, AS 'artist' }
   LEFT JOIN { $_->cds, AS 'cd' }
          ON { $_->cd->artistid eq $_->artist->id }
 );
-DwarnL render_expr(
+DwarnL to_sql(
   SELECT { $_->artist->name } WHERE { $_->artist->age > 25 }
 );
-DwarnL render_expr(
+DwarnL to_sql(
   SELECT { $_->cd->name }
   FROM { $_->cds, AS 'cd' }
   JOIN { $_->artists, AS 'artist' }
     ON { $_->cd->artistid eq $_->artist->id }
   WHERE { $_->artist->age > 25 }
 );
-DwarnL render_expr(ORDER BY { $_->foo, $_->bar, $_->baz } DESC);
+DwarnL to_sql(ORDER BY { $_->foo, $_->bar, $_->baz } DESC);
 
 my $basic = SELECT { $_->cd->name } FROM { $_->cds, AS 'cd' };
 
-DwarnL render_expr(
+DwarnL to_sql(
   FROM { $basic } WHERE { $_->year > 2000 }
 );
 
-DwarnL render_expr(
+DwarnL to_sql(
   FROM { $basic } ORDER BY { $_->year }
 );
 
-DwarnL render_expr(
+DwarnL to_sql(
   SELECT { $_->cd->name } FROM { $_->cds, AS 'cd' } ORDER BY { $_->year }
 );
 
-$renderer = Moo::Role->create_class_with_roles(
-  'Data::Query::Renderer::SQL::Naive',
-  'Data::Query::Renderer::SQL::Slice::LimitOffset'
-)->new;
-
-DwarnL render_expr(
+my $lo = 
   SELECT { $_->cd->name }
   FROM { $_->cds, AS 'cd' }
   ORDER BY { $_->year }
-  LIMIT { 10 } OFFSET { 10 }
-);
+  LIMIT { 10 } OFFSET { 10 };
+
+sub render_orders {
+
+  $renderer = make_renderer('LimitOffset');
+
+  DwarnL to_sql($lo);
+
+  $renderer = make_renderer('RowNum');
+
+  DwarnL to_sql($lo);
+
+  $renderer = make_renderer('RowNumberOver');
+
+  DwarnL to_sql($lo);
+
+}
+
+render_orders();
+
+$lo =
+  SELECT { $_->cd->name, $_->artist->name }
+  FROM { $_->cds, AS 'cd' }
+  JOIN { $_->artists, AS 'artist' }
+    ON { $_->cd->artistid eq $_->artist->id }
+  WHERE { $_->artist->age > 25 }
+  ORDER BY { $_->artist->age, $_->cd->id }
+  LIMIT { 10 } OFFSET { 20 };
+
+render_orders();