CICS经典教程.pptVIP

Relative Record Data Set(RRDS) A relative record data set has fixed-length slots, predefined to VSAM, in which records may be stored. A record in an RRDS is identified by the relative record number(RRN) of the slot that holds it 例：SO.VRSOWH.VR SO.VRSOWH.VR.DATA EXEC CICS READ DATASET(VRSOWH) INTO(SOWHRCD1) RIDFLD(RRN-0001) LENGTH(LGTH-701) UPDATE RRN END-EXEC. Empty Data Sets An empty data set is a data set that has not yet had any records written to it. CICS allow you to use an empty data set in the same way as you use a normal data set VSAM Alternate Indexes VSAM allows KSDS and ESDS(but not RRDS) data sets to have alternate keys To access records using an alternate key, you must define a further VSAM object, an alternate index path. 例： SS.VKSSLC.VK SS.VKSSLC.VK.DATA SS.VKSSLC.VK.IDX SS.VKSSLC.VK1.AIX SS.VKSSLC.VK1.AIX.DATA SS.VKSSLC.VK1.AIX.IDX SS.VKSSLC.VK1.PATH EXEC CICS HANDLE CONDITION NOTFND(240-END-EXEC-FUNC-LC) ENDFILE(240-END-EXEC-FUNC-LC) END-EXEC. 240-MOVE-MAP-LC-0. EXEC CICS STARTBR DATASET (VKSSCP1) RIDFLD (XLC-KEY-SLC) GTEQ END-EXEC. 240-MOVE-MAP-LC-1. EXEC CICS HANDLE