1 files changed, 124 insertions, 0 deletions
diff --git a/FS/FS/h_Common.pm b/FS/FS/h_Common.pm
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+++ b/FS/FS/h_Common.pm
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+package FS::h_Common;
+
+use strict;
+use FS::Record qw(dbdef);
+use Carp qw(confess);
+
+=head1 NAME
+
+FS::h_Common - History table "mixin" common base class
+
+=head1 SYNOPSIS
+
+package FS::h_tablename;
+@ISA = qw( FS::h_Common FS::tablename ); 
+
+sub table { 'h_table_name'; }
+
+sub insert { return "can't insert history records manually"; }
+sub delete { return "can't delete history records"; }
+sub replace { return "can't modify history records"; }
+
+=head1 DESCRIPTION
+
+FS::h_Common is intended as a "mixin" base class for history table classes to
+inherit from.
+
+=head1 METHODS
+
+=over 4
+
+=item sql_h_search END_TIMESTAMP [ START_TIMESTAMP ] 
+
+Returns an a list consisting of the "SELECT", "EXTRA_SQL", SQL fragments, a
+placeholder for "CACHE_OBJ" and an "AS" SQL fragment, to search for the
+appropriate history records created before END_TIMESTAMP and (optionally) not
+deleted before START_TIMESTAMP.
+
+=cut
+
+sub sql_h_search {
+  my( $self, $end ) = ( shift, shift );
+
+  my $table = $self->table;
+  my $real_table = ($table =~ /^h_(.*)$/) ? $1 : $table;
+  my $pkey = dbdef->table($real_table)->primary_key
+    or die "can't (yet) search history table $real_table without a primary key";
+
+  unless ($end) {
+    confess 'Called sql_h_search without END_TIMESTAMP';
+  }
+
+  my( $notdeleted, $notdeleted_mr ) = ( '', '' );
+  if ( scalar(@_) && $_[0] ) {
+    $notdeleted =
+      "AND 0 = ( SELECT COUNT(*) FROM $table as notdel
+                   WHERE notdel.$pkey = maintable.$pkey
+                     AND notdel.history_action = 'delete'
+                     AND notdel.history_date > maintable.history_date
+                     AND notdel.history_date <= $_[0]
+               )";
+    $notdeleted_mr =
+      "AND 0 = ( SELECT COUNT(*) FROM $table as notdel_mr
+                   WHERE notdel_mr.$pkey = mostrecent.$pkey
+                     AND notdel_mr.history_action = 'delete'
+                     AND notdel_mr.history_date > mostrecent.history_date
+                     AND notdel_mr.history_date <= $_[0]
+               )";
+  }
+
+  (
+    #"DISTINCT ON ( $pkey ) *",
+    "*",
+
+    "AND history_date <= $end
+     AND (    history_action = 'insert'
+           OR history_action = 'replace_new'
+         )
+     $notdeleted
+     AND history_date = ( SELECT MAX(mostrecent.history_date)
+                            FROM $table AS mostrecent
+                            WHERE mostrecent.$pkey = maintable.$pkey
+			      AND mostrecent.history_date <= $end
+			      AND (    mostrecent.history_action = 'insert'
+			            OR mostrecent.history_action = 'replace_new'
+				  )
+			      $notdeleted_mr
+                        )
+
+     ORDER BY $pkey ASC",
+     #ORDER BY $pkey ASC, history_date DESC",
+
+     '',
+
+     'AS maintable',
+  );
+
+}
+
+=item sql_h_searchs END_TIMESTAMP [ START_TIMESTAMP ] 
+
+Like sql_h_search, but limited to the single most recent record (before
+END_TIMESTAMP)
+
+=cut
+
+sub sql_h_searchs {
+  my $self = shift;
+  my($select, $where, $cacheobj, $as) = $self->sql_h_search(@_);
+  $where .= ' LIMIT 1';
+  ($select, $where, $cacheobj, $as);
+}
+
+=back
+
+=head1 BUGS
+
+=head1 SEE ALSO
+
+L<FS::Record>, schema.html from the base documentation
+
+=cut
+
+1;
+