diff --git a/htdocs/install/mysql/migration/3.6.0-3.7.0.sql b/htdocs/install/mysql/migration/3.6.0-3.7.0.sql
index 2efb6996993f378acce6d42fd3532f0353835cf0..d9d972cc25c282f3c7ebf931e3da547805b56a70 100755
--- a/htdocs/install/mysql/migration/3.6.0-3.7.0.sql
+++ b/htdocs/install/mysql/migration/3.6.0-3.7.0.sql
@@ -1095,6 +1095,9 @@ ALTER TABLE llx_projet_task_time ADD INDEX idx_projet_task_time_task (fk_task);
 ALTER TABLE llx_projet_task_time ADD INDEX idx_projet_task_time_date (task_date);
 ALTER TABLE llx_projet_task_time ADD INDEX idx_projet_task_time_datehour (task_datehour);
 
+ALTER TABLE llx_projet_task CHANGE COLUMN duration_effective real DEFAULT 0 NULL;
+ALTER TABLE llx_projet_task CHANGE COLUMN planned_workload real DEFAULT 0 NULL;
+  
 
 -- add extrafield on ficheinter lines
 CREATE TABLE llx_fichinterdet_extrafields
diff --git a/htdocs/install/mysql/tables/llx_projet_task.sql b/htdocs/install/mysql/tables/llx_projet_task.sql
index 98c8845974e1bb321a454b17e1b459c422725823..5b9decd23ef757b6df527816def4a29290d78115 100644
--- a/htdocs/install/mysql/tables/llx_projet_task.sql
+++ b/htdocs/install/mysql/tables/llx_projet_task.sql
@@ -31,10 +31,10 @@ create table llx_projet_task
   datev					datetime,						-- date validation
   label					varchar(255) NOT NULL,
   description			text,
-  duration_effective	real DEFAULT 0 NOT NULL,
-  planned_workload		real DEFAULT 0 NOT NULL,
-  progress				integer	DEFAULT 0,				-- percentage increase
-  priority				integer	DEFAULT 0,				-- priority
+  duration_effective	real DEFAULT 0,
+  planned_workload		real DEFAULT 0,
+  progress				integer DEFAULT 0,				-- percentage increase
+  priority				integer DEFAULT 0,				-- priority
   fk_user_creat			integer,						-- user who created the task
   fk_user_valid			integer,						-- user who validated the task
   fk_statut				smallint DEFAULT 0 NOT NULL,