diff --git a/htdocs/install/mysql/tables/llx_c_availability.sql b/htdocs/install/mysql/tables/llx_c_availability.sql
index 8dfd2e1d5d6..892b1b32f79 100644
--- a/htdocs/install/mysql/tables/llx_c_availability.sql
+++ b/htdocs/install/mysql/tables/llx_c_availability.sql
@@ -23,7 +23,7 @@ create table llx_c_availability
 	rowid		integer	 	AUTO_INCREMENT PRIMARY KEY,
 	code		varchar(30) NOT NULL,
 	label		varchar(128) NOT NULL,
-	type_duration	char(1),
+	type_duration	varchar(1),
 	qty	    real,
 	active		tinyint 	DEFAULT 1  NOT NULL,
 	position    integer NOT NULL DEFAULT 0