Mainframe DB2 Interview Questions and Answers Part-3
RCT is expanded as Resource – Control Table and is defined in the DB2/CICS region. This is the component that comprises of features that are gathered through macros of DSNCRCT. RCT matches with the transaction ID that of CICS, with the authorization ID that of DB2. This should also be matched with plan ID.
22.) How can tablespace be moved to another DASD volume that is allocated for that tablespace?
Tablespace that you are using is allocated only to STOGROUP, then you can enter the command ALTER STOGROUP for adding as well as deleting volume. REORG TABLESPACE and RECOVER TABLESPACE are statements that are helpful in creating new STOGROUP that can point towards the new volume. ALTER tablespace and REORG and RECOVER are statements used for altering and recovering the tablespace allocated in the memory.
23.) What is the information associated with SYSIBM.SYSLINKS table?
This is the table that contains information on the links that exists between the tables created through referential constraints.
24.) Explain in detail about buffer manager and its functionalities?
Buffer manager can be considered as the component inside DB2 that 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.
25.) Explain about cursor stability?
Cursor stability is the property that tells the DB2 that the values of database that are read by making use of this application gets protected while the data is used.
26) How do you specify and use a cursor in a COBOL program? ï¿½
Use DECLARE CURSOR statement either in working storage or in procedure division(before open cursor), to specify the SELECT statement. Then use OPEN, FETCH rows in a loop and finally CLOSE.
27) What happens when you say OPEN CURSOR?
If there is an ORDER BY clause, rows are fetched, sorted and made available for the FETCH statement. Other wise simply the cursor is placed on the first row.
28) Is DECLARE CURSOR executable?
29) Can you have more than one cursor open at any one time in a program ? ï¿½
30) When you COMMIT, is the cursor closed? – drona db2 interview questions