Modul 3: Database Administration Flashcards
What does a database contain?
A database contains Tables, Tables contain Records, Records contain Fields, and a Field is an individual piece of data in a record.
What is a Table?
A table is a collection of records in the database
How is records defined?
Records are identified by a 32-character, globally unique ID, called a sys_id.
Each record corresponds to a row in a table.
How is fields defined?
Each field corresponds to a column in a table and represents individual pieces of data in a record.
Mention the three key Field Attributes
- A label
The label is a user-friendly term which allows people to identify the field in the user interface. - A name
The name is a unique term that the system uses to identify the field in scripts and automated business processes. - A value
The values are actual data.
What are reference fields and how are they identified?
Reference fields are identified with the reference lookup icon.
The reference lookup icon opens a dialog box for locating a record to reference, presented as a list of the referenced (target) table.
In which ways can tables be related to each other?
- One-to-Many: Within a table, a field can hold a reference to a record on another table. There are three one-to-many relationship field types:
1. Reference Fields
2. Glide List
3. Document ID Fields - Many-to-Many: Two or more tables can be related in a bi-directional relationship, so that the related records are visible from both tables in a related list.
- Database Views: Two tables can be joined virtually using the Database Views Plugin to allow for reporting on data that might be stored in more than one table. Database Views are read-only.
- Extensions: A table can extend another table. The extended table includes unique fields plus all of the fields and their properties from the parent table.
What is a table that extends another table?
A Child Class. And the table it extends is the Parent Class.
Mention two parent tables that are extended to child classes
Task table
Configuration table
are examples of parent tables
If a table is extended but itself is not extending another table, it is called a:
Base table
Tables that exist in the base system are called:
Core tables
Tables that are created and do not exist in the base system are:
Custom tables
Hvad kendetegner at tabellen er Custom?
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What is a Schema Map?
The Schema Map provides a graphical representation of other tables related to a specifik table. This tool is available to Admin users.
What is an Access Control?
An Access Control is a security rule defined to specify which user are granted access. It is executed when attempting to access any ServiceNow table and may be set at the: Row-level and/or Column-level. Most security settings are implemented using Access Controls.