vsam การใช้

• VSAM is the physical access method used in DB2.
• VSAM records can be of fixed or variable length.
• The MVS Master Catalog " must " be a VSAM catalog.
• This permits generalised sharing of VSAM data.
• VSAM data sets consist of control intervals ( CI ) and control areas ( CA ).
• Programmers utilize various access methods ( such as QSAM or VSAM ) in programs for reading and writing data sets.
• Surround technology ( such as JCL, CICS, DB2, IMS, and VSAM ) is included in the scan process.
• But the Swiss machine and metal workers union, VSAM, said it expected sweeping cuts among the 150, 000 employees worldwide.
• As a VSAM data set, the KSDS data and index components consist of control intervals which are further organized in control areas.
• As such, VTAM is comparable with VSAM, which was at that time a new and supposedly converged access method for disk storage.
• Control Areas are the units of allocation so, when a VSAM data set is defined, an integral number of Control Areas will be allocated.
• These VSAM formats became the basis of IBM's database management systems, DB2-usually ESDS for the actual data storage and KSDS for indexes.
• VSAM also provides a catalog facility which enables applications to access files by name, without needing to know which disk drive ( s ) they are on.
• Switzerland's VSAM labor union said ABB employees should not be forced to pay for management mistakes and demanded to know where the jobs were to be cut.
• A "'Relative Record Data Set "'( RRDS ) is a type of data set organization used by the VSAM computer data storage system.
• For example, it can read sequential files based on the input format specified, then look up certain fields in a VSAM file or in another sequential file.
• Fast path DEDBs can only be built atop VSAM . DL / I databases can be built atop either VSAM or OSAM, with some restrictions depending on database organization.
• Fast path DEDBs can only be built atop VSAM . DL / I databases can be built atop either VSAM or OSAM, with some restrictions depending on database organization.
• However, most BDAM data sets did not and the incentive to move from BDAM to VSAM RRDS was much less compelling than that to move from ISAM to VSAM KSDS.
• However, most BDAM data sets did not and the incentive to move from BDAM to VSAM RRDS was much less compelling than that to move from ISAM to VSAM KSDS.