Interview Questions and Answers PDF

No. Because you cannot insert records in an ESDS, also when you rewrite a record, it must be of the same length. Thus putting any value for FREESPACE does not make any sense.

Value of 2 for cross region means that the file can be processed simultaneously by multiple users provided only one of them is an updater. Value of 3 for cross system means that any number of jobs can process the file for input or output (VSAM does nothing to ensure integrity).

DEFINE ALTERNATEINDEX. Important parameters are RELATE where you specify the base cluster name, KEYS, RECORDSIZE, SHAREOPTION, UNIQUEKEY (or NONUNIQUEKEY), DATA (DS NAME for the data component), INDEX(DS name for the index component). Then DEFINE PATH. Important parameters are NAME (DS name for the path). PATHENTRY (DS name of the alternate index name). UPDATE (or NOUPDATE) which specifies whether an ALT index is updated when a update to the vase cluster takes place. Then BLDINDEX. Paramters are INDATASET (DS name of base cluster), OUTDATASET (DS name of AIX).

They are end of file (10), duplicate key (22), record not found (23), VSAM logic error (90), open problem (92) and space problem (93).

A relative record dataset (RRDS) consists of a specified number of areas called slots. Each slot is identified by a relative record number (RRN) which indicates its relative position in the file.

ALTER modifies information for a catalog, alternate index, cluster or path. BLDINDEX builds the alternate index, of course. DEFINE is used for ALTERNATEINDEX, CLUSTER or PATH. DELETE removes the catalog entry for a catalog, cluster, alternate index or path. LISTCAT lists information about the dataset. PRINT prints the dataset contents. REPRO copies records from one file to another.

It specifies how the file may be shared between jobs and between batch and CICS environments.

The File STATUS clause of the FILE-CONTROL paragraph allows for each file to be associated with a file status key (i.e., the 2-character data item specified in the FILE STATUS clause). If the FILE STATUS clause is specified for a given file, a value indicating the status of each I/O operation against that file is placed in the associated file status key. This value is stored in the file status key as soon as the I/O operation is completed (and before execution of any EXCEPTION/ERROR declarative or INVALIDKEY/AT END phrase associated with the I/O request). Note : This element may behave differently when the CMPR2 compiler option is used. The file status key is divided into two status keys: the first character is known as file status key1; the second character is file status key 2.

It must be opened as I/O.

The RECOED KEY in the SELECT clause identifies the files primary key as it will be known to the program.

The ORGANIZATION is INDEXED.

The base cluster consists of the data component and the index component for the primary index of a KSDS.

Free space is reserved within the data component of a KSDS to accommodate inserting new records.

A path is a file that allows you to access a file by alternate index – the path provides an association between the AIX and the base cluster.

A control interval is the unit of information that VSAM transfers between virtual and auxilliary storage.

A group of control intervals makes up a control area.

This is the other part of the index. It has multiple levels with pointers that ultimately reach to the sequence set.

The catalog contains the name of all datasets. VSAM and non-VSAM. It is used to access these datasets.

The FILE STATUS field identifies the field that VSAM uses to provide information about each I/O operation for the file.

ACCESS can be SEQUENTIAL, RANDOM or DYNAMIC.