Understanding/Viewing Database Schema

[StacyLen]

I am trying to find a way to read/understand the database schema for Servicenow.  When I go to Tables & Columns and look at schema maps, they are so huge, it seems impossible to follow them on a computer monitor. 

Bottom line, I need to know what are the primary and foreign keys relating one table to another.  Simple example might be Requests and Request Items.  I know there has to be a quick way to find such keys, but I dont know the way.

Any help appreciated

Stacy Whetzell

[Maik Skoddow · Accepted solution]

Hi @StacyLen 

yes OOTB you have the schema map tool. See https://docs.servicenow.com/bundle/vancouver-platform-administration/page/administer/table-administr... for more information.

Maik

[Maik Skoddow]

Hi @StacyLen 

an OOTB ServiceNow already has over 4000 tables in place and after loading some heavy modules you will find more than 10000 tables typically. You cannot get a simple view on such a huge amount of tables, and your only chance is to into detail where required.

Next important thing to know: ServiceNow is encapsulating the database level completely and therefore we don't talk about primary & foreign keys in ServiceNow as these words relate to concepts on the database level. In ServiceNow we have "Reference" fields, and you can "follow" when having a look onto the table structure. You can reach this information either via the "Dictionary" module or by selecting "Table" from the table header options:

This approach is helpful for the outgoing direction of references. But if you want to know which other tables are referencing to the current table, you have to leverage the table schema tool.

Let me know if this was not helpful.

Maik

[StacyLen]

Thanks @Maik Skoddow 

Is there a tool that if I enter two table names it will show me the Reference fields that connect them (if they are connected).

Thank you again Maik

[Maik Skoddow · Accepted solution]

Hi @StacyLen 

yes OOTB you have the schema map tool. See https://docs.servicenow.com/bundle/vancouver-platform-administration/page/administer/table-administr... for more information.

Maik

[StacyLen · Accepted solution]

Thank you big time Maik