VSAM Interview Questions and Answers For Experienced | Mostly Asked in An Interview | Mainframe Guru
FAQ
What are the 4 types of VSAM files?
VSAM supports several data set types: entry-sequenced (ESDS), key-sequenced (KSDS), linear (LDS), fixed-length, and variable-length relative record (RRDS).
What is VSAM used for?
Virtual storage access method (VSAM) is an access method for files on direct-access storage devices. With VSAM you can load files, retrieve records from files, update files, and add, replace, and delete records in files. VSAM processing has these advantages over QSAM: Protection of data against unauthorized access.
How do I identify a VSAM file?
You can identify records in data sets by key , by relative byte address (RBA) or extended relative byte address (XRBA) , or by relative record number (RRN) .
What is the difference between VSAM and flat file?
VSAM is a file access method. The acronym stands for Virtual Storage Access Method. VSAM offers faster access than flat files because it uses an inverted index (B+tree). The index is used to access the data faster than simply reading every record until the right one is found.
