Conditionally move MySQL data between rows in same table - mysql

Question

Working in Redmine, I need to copy(not move) data from certain rows to other rows based on matching project id numbers with time entries.
I have included a diagram of the table "custom_values" and my understanding of the design below(CURRENT DATA):
+----+-----------------+---------------+-----------------+-------+
| id | customized_type | customized_id | custom_field_id | value |
+----+-----------------+---------------+-----------------+-------+
| 1 | Project | 1 | 1 | 01 |
| 2 | TimeEntry | 1 | 4 | 01 |
| 3 | Project | 2 | 1 | 02 |
| 4 | TimeEntry | 2 | 4 | 02 |
| 5 | Project | 3 | 1 | 03 |
| 6 | TimeEntry | 3 | 4 | |
| 7 | Project | 4 | 1 | 04 |
| 8 | TimeEntry | 4 | 4 | |
+----+-----------------+---------------+-----------------+-------+
At the risk of oversimplifying,
"id" = The primary key for each entry in custom_values
"customized_type" = Specifies which db table the row is referring to.
"customized_id" = Specifies the primary key for the db table entry previously specified in "customized_type".
"custom_field_id" = Specifies which custom field the row is referring to. Redmine admins can arbitrarily add and remove custom fields.
"value" = The data contained within the custom field specified by
"custom_field_id"
In my situation, the values listed in "value" are representing unique customer id numbers. The customer id numbers did not always get entered with each time entry. I need to copy the customer numbers from the project rows to the matching time entry rows. Each time entry has a project_id field.
So far, here is my mangled SQL query:
SELECT
custom_field_id,
custom_values.value AS 'CUSTOMER_NUMBER',
custom_values.customized_id AS 'PROJECT_ID_NUMBER',
custom_values.customized_type,
time_entries.comments AS 'TIME_ENTRY_COMMENTS'
FROM
redmine_tweaking.custom_values
LEFT JOIN
redmine_tweaking.time_entries ON custom_values.customized_id = time_entries.project_id
WHERE
custom_values.customized_type='Project' AND custom_values.custom_field_id=1;
The query I have so far allows me to see that I have the time entries connected properly to their matching projects, but that is all I have been able to figure out. So in other words, this SQL statement does not exactly solve my problem.
Plus, even if it did work, I think the way I laid it out looks like 200 lbs of bird poop. There must be a better/more optimized way to do this.
Any help would be greatly appreciated. I am relatively new and I have been pouring hours into solving this problem.
UPDATE:
Ok, here is the time_entries table:
+----+------------+---------+----------+-------+----------+-------------+------------+-------+--------+-------+---------------------+---------------------+
| id | project_id | user_id | issue_id | hours | comments | activity_id | spent_on | tyear | tmonth | tweek | created_on | updated_on |
+----+------------+---------+----------+-------+----------+-------------+------------+-------+--------+-------+---------------------+---------------------+
| 1 | 1 | 1 | 1 | .25 | test | 9 | 2015-11-04 | 2015 | 11 | 45 | 2015-11-04 08:18:12 | 2015-11-04 10:18:12 |
| 2 | 2 | 1 | 1 | .25 | test2 | 9 | 2015-11-04 | 2015 | 11 | 45 | 2015-11-04 09:18:12 | 2015-11-04 12:18:12 |
+----+------------+---------+----------+-------+----------+-------------+------------+-------+--------+-------+---------------------+---------------------+
As opposed to the original table that I first posted, the expected output would show this:
+----+-----------------+---------------+-----------------+-------+
| id | customized_type | customized_id | custom_field_id | value |
+----+-----------------+---------------+-----------------+-------+
| 1 | Project | 1 | 1 | 01 |
| 2 | TimeEntry | 1 | 4 | 01 |
| 3 | Project | 2 | 1 | 02 |
| 4 | TimeEntry | 2 | 4 | 02 |
| 5 | Project | 3 | 1 | 03 |
| 6 | TimeEntry | 3 | 4 | 03 |
| 7 | Project | 4 | 1 | 04 |
| 8 | TimeEntry | 4 | 4 | 04 |
+----+-----------------+---------------+-----------------+-------+