facing Issue while copying records from parent table A to child table B (extends A)

[shreyanshs07]

hello community, 

Recently I faced this issue while copying records from parent table 'u_table_a' (created by me) to child table 'u_table_b' (also created by me). I created a script include to copy those records from parent table to child table and when running that script in background script, the records are getting copied to the parent table itself and not in the child table.

above is the screenshot of the script include which I created.

above are the parent table records which I want to copy.

after running the script include, the records are getting copied to the parent table and not the child table.

[Bert_c1 · Accepted solution]

This may expected due to the proprietary database schema in servicenow, see:

table-administration

if 'u_table_a' is not extended from any table, then the check you have for a valid column in 'u_table_b' is not needed. As 'u_table_b' contains all of the columns form 'u_table_a'. You can leave out the 'isValidField()' check.

Look at each table definition in sys_db_object, see that all fields on u_table_a are present on u_table_b.  Also, post script as text and then others here can copy and test. I don't see any problems by eye with the script logic.

And I just confirmed, that when creating a record in table b, the parent record is created in table a. so no need for your script.

Try the following in scripts background:

var sda = new GlideRecord('sys_dictionary');
sda.addQuery('name', 'u_table_a');
sda.query();
while (sda.next()) {
	gs.info('Table: ' + sda.name + ', element: ' + sda.element);
}

var sdb = new GlideRecord('sys_dictionary');
sdb.addQuery('name', 'u_table_b');
sdb.query();
while (sdb.next()) {
	gs.info('Table: ' + sdb.name + ', element: ' + sdb.element);
}

the results in the database are:

*** Script: Table: u_table_a, element: sys_updated_on
*** Script: Table: u_table_a, element: sys_id
*** Script: Table: u_table_a, element: sys_created_by
*** Script: Table: u_table_a, element: u_field_1
*** Script: Table: u_table_a, element: sys_created_on
*** Script: Table: u_table_a, element: 
*** Script: Table: u_table_a, element: sys_updated_by
*** Script: Table: u_table_a, element: sys_mod_count
*** Script: Table: u_table_a, element: sys_class_name
*** Script: Table: u_table_b, element: 
*** Script: Table: u_table_b, element: sys_id
*** Script: Table: u_table_b, element: u_table_field

The UI shows Table A's fields when viewing a record in Table B. But the database need not duplicate the table column names.

[debendudas · Accepted solution]

Hi @shreyanshs07 ,

You can use the below script to copy record from parent table to child table:

var parentGr = new GlideRecord("u_table_a");
parentGr.query();
while (parentGr.next()) {
   parentGr.sys_class_name = "u_table_b";
   parentGr.insert();
}

If this solution helps you then, mark it as accepted solution ‌‌✔️ and give thumbs up 👍! 

[shreyanshs07]

Thank you for the script @debendudas , could you please also explain in brief what is 'sys_class_name' as I have not used it much and in what scenarios can it be used?

[debendudas]

Hi @shreyanshs07 ,

sys_class_name is the system field present on the table which basically gives the table name.

Please check this community post for more information: What is sys_class_name? - ServiceNow Community