Tutorial To Understand Tables in ServiceNow | ServiceNow Tables

This article will provide you brief about the tables in ServiceNow. ServiceNow have different types of tables some of known as base table, core table, custom tables etc. Each and every table in ServiceNow have a specific features. In ServiceNow each and every applications is having tables. So Understanding of ServiceNow tables is really very important for any ServiceNow professional. In this article you will get complete understanding of Custom, core and base table in ServiceNow. Along with this video demonstration has been given below which will provide you complete understanding about ServiceNow Table and their creation. 

In ServiceNow whatever we do, such as create any thing either table, record, label, write code etc. or modify any data such as record, table, code etc. or update any thing in ServiceNow each and every thing will store in table. In ServiceNow there are hundreds of tables which are taking care of all above stuff. In this article we will talk about these type of tables.

In this article, I am going to cover below points:

• What is Table in ServiceNow?
• What is base table in ServiceNow, name some of the base table in ServiceNow ?
• What is core table in ServiceNow and Difference between base table  and core table in ServiceNow?
• What is custom table in ServiceNow?
• How to create table in ServiceNow or custom table in ServiceNow?
• What does Table extend another Table means in ServiceNow?
• What all field or columns gets auto populated when we create table in ServiceNow?
• How to find total number of table available in ServiceNow?
• What is system table in ServiceNow?
• What is table schema and how to see table schema?

What is a table in ServiceNow?

Relational data is stored in records and collection of records forms a table or we can say that table is a collection of records. Table is composed of field and records that holds data and consist of row and columns.

Above relational data means that name field will contain the name and address field will contain the address etc. If name contains the address than it is not said to relational.

In ServiceNow applications whatever we do such as creating incident ticket, problem ticket, change ticket, approving any record, creating or modifying any record, creating new table etc. Means whatever we do in ServiceNow application is stored in any of the table. For e.g. if we create new table then that entry will get stored in ‘sys_db_object’ table.

In ServiceNow there are hundreds of tables and all the tables are connected to each other means they are having a relationship of any kind, such as some tables are extended by some tables and some tables are extending other tables. For e.g. incident table is extending task table and task table is extended by incident table, problem table, change table etc.

In ServiceNow, tables are categorized such as base table, core table, custom table, system table or database view table etc.

Note that it is not possible to extend system tables or database view tables

So Now let’s talk about these tables.

What is base table in ServiceNow, name some of the base table in ServiceNow?

Table which would not extend any table and can be extensible is said to be base table. Some of the base table are: cmdb, task, task_activity, cmdb_model etc.For e.g.

task table did not extend any table, but task table is extended by many tables such as incident, change, problem etc.

cmdb table did not extend any table but it is extended by cmdb_ci table.

What is core table in ServiceNow and Difference between base table core table in ServiceNow?

As per my understanding, table which exist in base system is said to be core table. To understand it in details:

 Let’s say you are working on change management application and you have created or modified change record in change module than that change data of creation will be saved or updated in “change_request” table so “change_request” is core table of change management. Same as for problem management, problem is core table, same as for incident management, incident is core table. This applies to all the applications in servicenow.

Other then this, incident table extends task table right, it means task table provides series of standard fields which is used by incident table. So, this type of table which is extended by other tables and their standard field is used by extended table is also said to be core table. For e.g. task and cmdb_ci tables, whereas task table is base table as well as core table both.

So,the difference between base table and core table in servicenow is that Base table may be a core table (for e.g. task), but it is not necessary that core table is always to be a base table (for e.g. incident and problem).

What is custom table in ServiceNow?

Custom table is a table which is created by ServiceNow system administrator or ServiceNow developer by their own and it is not provided by ServiceNow platform. Let’s say table such as incident, task, cmdb,cmdb_ci, problem etc are provided by ServiceNow platform. But custom table we have to create by our own and it start with prefix “u_” for e.g “u_demotable”. We can also say custom tables as non-ServiceNow tables. You may navigate to below link for more understanding on custom table:

ServiceNow Documents

How to create table in ServiceNow or custom table in servicenow?

Below are the steps to create custom table:

Type tables in left filter navigator:

Click on New Button and create new table as mentioned in screenshots:

ServiceNow Table Picture

In this way we can create new table in ServiceNow. If we extends the table from extend table field then above table will also contains the field of extended table.

What all field or columns gets auto populated when we create table in servicenow?

There are six fields which get created automatically, fields or column  are: created by, created, sys id, updates, updated by and updated.

What does Table extend another Table means in ServiceNow?

If X table extends the Y table then it means that X table inherits the Y Table columns and X table consider as child class and Y table consider as parent class in servicenow.

For e.g. Incident table extends the task table, cmdb_ci_hardware extends cmdb_ci_computer table etc.

How to find total number of table available in ServiceNow?

Two ways to find only from navigating to application:

You can directly navigate to table module and filter the list view with filter all.

Type sys_db_object.list in filter navigator left side and click enter. Actually sys_db_object table contains a record for each table in the database

What is system table in servicenow?

System table start with prefix “sys_” and it is by default, restricted from the Reporting module

What is table schema and how to see table schema?

The table schema is actually  a map which displays the details of tables and their relationships. For e.g. if we see the schema map of cmdb_ci table then it will tell us that what all tables are extending cmdb_ci table and what all table is extended by cmdb_ci.

We can see schema form two different places such as from tables & columns module and from table itself from related link.

Below are the steps to see schema of any table:

1. Through "Tables & Columns" module:

Navigate to System Definition --> Table and Columns and click on Tables & Columns module and as displayed in below image select the table and click on schema map button.

Once you clicked you will navigate to below page where you find that what all tables are referenced, table referencing, extended and extending.

2. Through "Tables" module:

1. Type “Tables” in left filter navigator.
2. Search for table, let’s say type Configuration Item in label section and press enter.
3. Open the table and navigate bottom as displayed below, under related link click on show schema map.

So as mentioned above in screenshot you can see the relationships between the tables in ServiceNow.

Let Talk about Child Table and Parent Table in ServiceNow in Detail:

As we know when we create a new table in ServiceNow and extend any table, for e.g. lets say task table then all the field available in the task table will also be available in the newly created child table. Now there are two things in table one is field and another is data. 

So if we talk about field than  field go to child from parent and when we talk about data then data goes to parent from child. For e.g.  All the data which we create in child table will also get displayed in Parent table because child table is extending parent table.

But for e.g. child table has custom field which is not extended from the parent table then created child record will get displayed in parent table except the date of that custom field. let say child table has field 

Customer Phone Number" which is a not extended from parent table. Then when we see record in parent table then "Customer phone number" will not displayed there.

I hope the above article helps you to understand the ServiceNow table basics.

You can also refer below video for more understanding that how to create table in ServiceNow, what is table schema and difference between core table, base table and custom table in ServiceNow.

Video Tutorial to Understand ServiceNow Tables :

We hope the information shared above related to different type of ServiceNow table will be helpful for you and helps you to create and understand different type of tables in ServiceNow. Please feel free to share your feedback below and let us know if you have questions in ServiceNow Tables concepts. We will try our best to answer all of your queries. For more ServiceNow concepts you can also refer our YouTube channel Basico ServiceNow Learning.