A table space is a logical entity in DB2 architecture. It is basically a collection of data files. A tablespace contains tables, indexes, objects, etc. To create a new tablespace we have to issue the following command.CREATE TABLESPACE TABSPA1    IN DBSET1    USING STOGROUP STG1    PRIQTY 50   ... Read More

A database is a structured collection of data which can be organized, maintained and updated easily. There can be multiple databases in a DB2 installation. The DB2 database can be created by giving the name of the database, storage group and bufferpool, as below−CREATE DATABASE DBSET1       STOGROUP ... Read More

Storage groups are basically the collection of volumes which hold the data that is present in the DB2 table. Basically it is the responsibility of DBA to maintain, add and update the storage groups in DB2.To create a storage group in a DB2 installation we have to give below command.CREATE ... Read More

The access path gives us the path selected by the optimizers in order to fetch the result of the SQL query. It gives us an idea about what all indexes and parameters will be used by the optimizer.To get the details of the access path used for the SQL statements ... Read More

The isolation level defines the degree to which the DB2 data which is being accessed in the COBOL-DB2 program is isolated with another parallelly executing COBOL- DB2 program. There are 4 main types of Isolation levels in DB2.Cursor stability (CS) - The cursor stability isolation level locks only the current ... Read More

The COBOL-DB2 program can place the lock into a DB2 table in two ways.When the SQL statement using that table is executed within the program.When the program is loaded in the main memory and it is ready to be executed. It acquires a lock on all the DB2 tables which ... Read More

The locks in DB2 are acquired on table and tablespaces to avoid the issues arising due to LOST UPDATE, DIRTY READ and PHANTOM.We need to define the lock parameter during the BIND package/plan step using the ACQUIRE option.A COBOL-DB2 program PROGA is using SQL statements to access table TA. If ... Read More

To prepare a COBOL-DB2 program for execution, we have to go through certain steps. These steps include pre-compilation - compilation - binding - linkediting.The pre-compilation is done using the utility DSNHPC. In the pre-compilation step all the SQL statements which are present in the source program are replaced by corresponding ... Read More

In each execution of a COBOL-DB2 program, the timestamp of load module and package/DBRM are compared. If there is a change in the length of the variable (and no SQL change) in the program and it is compiled, then the load module will have the newly generated timestamp and on ... Read More

The program will run successfully (unless there are no logical errors in the program)because the timestamp is inserted in the DBRM during pre-compilation and pre-compilation is done before the compilation step. Therefore, the DBRM and the load module will have the same timestamp.The timestamp inserted in the DBRM is further ... Read More