From 2dd9b10e6b57328ec6f9aed44f829f6eaa739688 Mon Sep 17 00:00:00 2001
From: Fridolin Somers <fridolin.somers@biblibre.com>
Date: Fri, 17 Jan 2020 10:25:19 +0100
Subject: [PATCH] Bug 24443: Consider NULL as 0 for issues in items search

In items search, we can filter by items issues count, data coming from items.issues.
Most of the time, for an item with no issues this column contains NULL.
This enhancement proposes to consider NULL as 0 to allow searching items with no issues.

Test plan:
1) Use SQL to count items with items.issues = NULL :
   select count(*) from items where issues is null;
2) Go to items search
3) Perform search with filter "Checkout count" = 0
4) Check you get the same number of results as SQL query
---
 C4/Items.pm | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/C4/Items.pm b/C4/Items.pm
index bd335d5563..4bd98a7bf8 100644
--- a/C4/Items.pm
+++ b/C4/Items.pm
@@ -2142,6 +2142,9 @@ sub _SearchItems_build_where_fragment {
                     }
                     $column = "ExtractValue($sqlfield, '$xpath')";
                 }
+            } elsif ($field eq 'issues') {
+                # Consider NULL as 0 for issues count
+                $column = 'COALESCE(issues,0)';
             } else {
                 $column = $field;
             }
-- 
2.24.1