Tera Data Interview Questions and Answers
Question - 91 : - What is FAST EXPORT in Teradata?
Answer - 91 : -
In Teradata FAST EXPORT refers to exports data from Teradata to a Flat file.
Question - 92 : - Teradata MultiLoad supports how many populated tables?
Answer - 92 : -
Teradata Multiload supports up to five populated tables.
Question - 93 : - What is Transient Journaling in Teradata?
Answer - 93 : -
The transient journal is a system-maintained dictionary table that provides a way to protect transactions from various system failures and from deadlock (see SQL Request and Transaction Processing for a description of deadlock). Each transaction processed by Teradata Database records a before change image of rows that are touched by the transaction.
Then if a transaction fails for some reason, the before change image of any modified rows can be retrieved from the transient journal and written over the modifications, returning the row to the same state it was in before the transaction occurred. Teradata Database removes all before change images from the transient journal after a transaction commits.
Question - 94 : - What are Database Privileges in Teradata?
Answer - 94 : -
A database privilege is permission to access or to manipulate a database object or data. Specific privileges are required for nearly everything that can be done in the Teradata Database.
Teradata Database privileges are used by administrators to control access to database objects and data and to control the types of actions and activities available to users.
The privileges are used to control which users can:
- Access, create, modify, or delete specific database objects and data
- Execute specific macros, stored procedures, and UDFs
- Monitor system-wide activity
- Grant privileges to other users
Question - 95 : - What are the Privilege Levels available in Teradata?
Answer - 95 : -
Teradata Database supports system-level, object-level, row-level, and zone-level privileges.
- System-level privileges
- Object-level privileges
- Database
- Table
- Row or column
- Other object types
- Row-level privileges
- Zone-level privilege
Question - 96 : - Explain the GRANT statement in Teradata?
Answer - 96 : -
GRANT establishes explicit privileges for one or more users, proxy users, databases, or roles.
Question - 97 : - What are the different GRANT forms available in Teradata?
Answer - 97 : -
In Teradata there are different GRANT forms are there, they are:
1. GRANT (Monitor Form) - Performance monitoring of Teradata Database.
2. GRANT (Role Form) - Granting role membership to users and other roles.
3. GRANT (SQL Form) - Granting access to, creation of, or logging off, various Teradata database objects.
4. GRANT ZONE - Granting zone guest status to users or roles that do not belong to any zone. GRANT ZONE does not automatically grant users access to database objects within the zone. Zone users must grant privileges to zone guests before access is permitted.
5. GRANT CONNECT THROUGH - Granting the ability to connect as a proxy permanent or proxy application user through a trusted user.
6. GRANT LOGON - Granting system logon privileges.
Question - 98 : - Explain the REVOKE statement in Teradata?
Answer - 98 : -
REVOKE rescinds explicit privileges from one or more users, proxy users, databases, or roles. The privileges might have been conferred either automatically or by a previous GRANT statement.
Question - 99 : - What is the purpose of the SHOW statement?
Answer - 99 : -
SHOW statements return the result of the last data definition statement performed against the named database object in the form of a CREATE database_object or ALTER database_objectstatement.
Question - 100 : - Difference between PRIMARY KEY Constraints Versus UNIQUE Constraints in Teradata?
Answer - 100 : -
- UNIQUE and PRIMARY KEY constraints can only be defined on a column set that is also constrained to be NOT NULL.
- To create a composite, or multicolumn, the primary key for a table, you must specify the PRIMARY KEY constraint at the table level, not the column level.
- Both UNIQUE and PRIMARY KEY constraints can be defined on a UDT column.
- Teradata Database also supports the related constraints UNIQUE INDEX and UNIQUE PRIMARY INDEX.