What does the "u_" prefix stands for?

[bielc_araujo]

I'm a newbie on ServiceNow and just got curious on what exactly the "u" prefix on custom fields stand for, anyone know?

[Dr Atul G- LNG · Accepted solution]

Hi @bielc_araujo 

u_ -> Custom Table in Global Scope

The "u_" prefix indicates a custom table and cannot be edited or deleted. The User role is the role required to access the new table.

X_ --> Custom table in scoped application

https://www.servicenow.com/community/spm-blog/4-tips-for-creating-custom-tables-in-servicenow/ba-p/2....

[AnubhavRitolia · Accepted solution]

Hi @bielc_araujo 

'u_' for field stands for custom field which was created by developer and not exist by default in ServiceNow.

[Brad Tilton · Accepted solution]

As others have said, the u_ indicates a global table created by a customer. The reason that exists is to prevent table naming collisions. We (ServiceNow) know the names of all of the default tables, but a customer could create a new custom table, let's say shipping_location, and then we could have a use case where we needed to create a table with that name and that would create a collision on upgrade. Instead, we just know to never create a table starting with u_.

The reason this only exists for global is because every scoped table name includes the company code (x_acme, for example) so those are unique by default.

Hope that helps, and keep asking great questions!

[Dr Atul G- LNG · Accepted solution]

Hi @bielc_araujo 

u_ -> Custom Table in Global Scope

The "u_" prefix indicates a custom table and cannot be edited or deleted. The User role is the role required to access the new table.

X_ --> Custom table in scoped application

https://www.servicenow.com/community/spm-blog/4-tips-for-creating-custom-tables-in-servicenow/ba-p/2....

[Brad Tilton · Accepted solution]

To clarify this answer a bit. A table with a u_ can be edited or deleted. There is no special security that the custom table has by default. The u_ just prevents collisions which means that your table won't be affected during an upgrade by SN introducing a table with the same name.

[RB5]

@bielc_araujo  - "u" prefix is used for the custom fields that has been created by user. It is used to distinguish between predefined system fields and custom fields created by users. It also helps to prevent naming conflicts with existing system fields.

ServiceNow also provides predefined prefix to indicates their purpose. For example "sys_” prefix fields are predefined system fields.  fields with cmdb_” prefix are related to configuration management etc.

-- Please mark this as correct answer and helpful.

[sprdave]

When creating a new table named "abc" in ServiceNow, does the system automatically assigns the table name as u_abc or do you have to manually set it as "u_"  I cannot find an answer to this question.