1) Give breif detail about DB2?
DB2 is a Relational Database Management System developed by IBM. It supports Object Oriented features and non-relational structures with XML.
2) Enlist the types of datatypes available in DB2?
3) What is Instance in DB2?
Instance is a logical Environment of DB2 Database Manager. It helps in managing database also, we can create multiple instance on one physical machine.
4) Enlist the content of instance directory.
- Database Manager Configuration file
- System Database Directory
- Node Directory
- Node Configuration File
- Debugging files, dump files
5) What is Bufferpool?
The Database Manager allocates some memory on the main memory space known as Bufferpool. It is designed to cache table and index data from disk.
6) Enlist the types of bufferpool.
7) What are "Dirty Pages"?
Pages in the bufferpool which are updated with data but not written onto the disk those pages are known as Dirty Pages.
8) What is tables in DB2 and give its types?
Tables is a logical structure maintain by database manager. It consist of Tuple which is column and Entity which is row. Types of tables are:
- Basic Tables
- Temporary Tables
- Materialized Query Tables
9) Describe DB2 constraint?
DB2 constraint is a set of rules which maintains database integrity. Here, are some types of constraint:
- NOT NULL
- Primary Key
- Foreign Key
- Unique Key etc.
10) What is the picture clause of Null indicator variable?
Picture clause of Null indicator variable is S9(4)COMP.
11) Define DCLGEN in DB2.
DCLGEN stands for Declaration Generator which describes a table or view for SQL statements.
12) What is the use of DB2 optimizer.
- It is used to process SQL Statements.
- To select the access path we uses DB2 optimizer.
13) What is SQLCA and its maximum length.
SQLCA (SQL Communication Area) is a structure of variable which is updated after each execution of SQL statements. Its maximum length is 136.
14) Explain DBRM in DB2.
DBRM stands for Database Request Model which is created by the pre-compiler of DB2. It consist of SQL source statements which is taken from application program.
15) Describe RCT.
RCT (Resource Control Table) which is defined in DB2/CICS region. It consist of the features which is gathered from macros of DSNCRCT.
16) What is DB2 bind?
The process that builds access paths to the DB2 table is known as bind. The bind uses Database Request Modules from the DB2 pre-compile step as input and produces an application plan.
17) Enlist types of page locks.
There are 3 types of page locks as enlisted below:
18) Define Predicate.
Predicate is the element of a search condition. Predicate is used to express or implies a search condition.
19) Explain Buffer Manager.
Buffer Manager helps in transferring data between virtual as well as external medium. The buffer manager reduces the quantity of physical input as well as output operations that are actually performed by making use of buffering techniques that are highly sophisticated.
20) What is cursor stability?
Cursor stability is the property that values of database that are read by making use of this application gets protected while the data is used.
21) What is RELEASE/ACQUIRE in BIND?
RELEASE in bind is used when we have to change the locks condition of the database for user. RELEASE helps in page locks to be free from cache memory.
22) What are different locking levels?
23) Explain component of DCLGEN.
There are two components of DCLGEN are:
- A copy book of the host language, which will give alternative definitions for all the column names.
- In terms of the data-types of DB2, EXEC SQL DECLARE TABLE shows an aesthetic layout of the table.
24) Explain SYSIBM.SYSLINKS table?
It is a table that contains information on the links that exists between the tables created through referential constraints.
25)What are the Isolation levels possible
- CS: Cursor Stability
- RR: Repeatable Read