diff --git a/htdocs/install/mysql/migration/15.0.0-16.0.0.sql b/htdocs/install/mysql/migration/15.0.0-16.0.0.sql
new file mode 100644
index 00000000000..64df9ca79cb
--- /dev/null
+++ b/htdocs/install/mysql/migration/15.0.0-16.0.0.sql
@@ -0,0 +1,34 @@
+--
+-- Be carefull to requests order.
+-- This file must be loaded by calling /install/index.php page
+-- when current version is 14.0.0 or higher.
+--
+-- To restrict request to Mysql version x.y minimum use -- VMYSQLx.y
+-- To restrict request to Pgsql version x.y minimum use -- VPGSQLx.y
+-- To rename a table:       ALTER TABLE llx_table RENAME TO llx_table_new;
+-- To add a column:         ALTER TABLE llx_table ADD COLUMN newcol varchar(60) NOT NULL DEFAULT '0' AFTER existingcol;
+-- To rename a column:      ALTER TABLE llx_table CHANGE COLUMN oldname newname varchar(60);
+-- To drop a column:        ALTER TABLE llx_table DROP COLUMN oldname;
+-- To change type of field: ALTER TABLE llx_table MODIFY COLUMN name varchar(60);
+-- To drop a foreign key:   ALTER TABLE llx_table DROP FOREIGN KEY fk_name;
+-- To create a unique index ALTER TABLE llx_table ADD UNIQUE INDEX uk_table_field (field);
+-- To drop an index:        -- VMYSQL4.1 DROP INDEX nomindex on llx_table;
+-- To drop an index:        -- VPGSQL8.2 DROP INDEX nomindex;
+-- To make pk to be auto increment (mysql):    -- VMYSQL4.3 ALTER TABLE llx_table CHANGE COLUMN rowid rowid INTEGER NOT NULL AUTO_INCREMENT;
+-- To make pk to be auto increment (postgres):
+-- -- VPGSQL8.2 CREATE SEQUENCE llx_table_rowid_seq OWNED BY llx_table.rowid;
+-- -- VPGSQL8.2 ALTER TABLE llx_table ADD PRIMARY KEY (rowid);
+-- -- VPGSQL8.2 ALTER TABLE llx_table ALTER COLUMN rowid SET DEFAULT nextval('llx_table_rowid_seq');
+-- -- VPGSQL8.2 SELECT setval('llx_table_rowid_seq', MAX(rowid)) FROM llx_table;
+-- To set a field as NULL:                     -- VMYSQL4.3 ALTER TABLE llx_table MODIFY COLUMN name varchar(60) NULL;
+-- To set a field as NULL:                     -- VPGSQL8.2 ALTER TABLE llx_table ALTER COLUMN name DROP NOT NULL;
+-- To set a field as NOT NULL:                 -- VMYSQL4.3 ALTER TABLE llx_table MODIFY COLUMN name varchar(60) NOT NULL;
+-- To set a field as NOT NULL:                 -- VPGSQL8.2 ALTER TABLE llx_table ALTER COLUMN name SET NOT NULL;
+-- To set a field as default NULL:             -- VPGSQL8.2 ALTER TABLE llx_table ALTER COLUMN name SET DEFAULT NULL;
+-- Note: fields with type BLOB/TEXT can't have default value.
+-- To rebuild sequence for postgresql after insert by forcing id autoincrement fields:
+-- -- VPGSQL8.2 SELECT dol_util_rebuild_sequences();
+
+
+-- Missing in v14 or lower
+ALTER TABLE llx_projet_task_time ADD COLUMN fk_product integer NULL;
diff --git a/htdocs/install/mysql/tables/llx_projet_task_time.sql b/htdocs/install/mysql/tables/llx_projet_task_time.sql
index 786d8907588..63eadb1177f 100644
--- a/htdocs/install/mysql/tables/llx_projet_task_time.sql
+++ b/htdocs/install/mysql/tables/llx_projet_task_time.sql
@@ -24,6 +24,7 @@ create table llx_projet_task_time
   task_datehour    datetime,				-- day + hour
   task_date_withhour integer DEFAULT 0,	-- 0 by default, 1 if date was entered with start hour
   task_duration    double,
+  fk_product       integer NULL,
   fk_user          integer,
   thm			   double(24,8),
   invoice_id       integer DEFAULT NULL,				-- If we need to invoice each line of timespent, we can save invoice id here