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]

Hi @sprdave 

System add u_ automatically when a table get created in global scope 

[sprdave]

Thank You!!

[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!