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SELECT operator z/OS DFSORT Application Programming Guide SC23-6878-00 |
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>>-SELECT--FROM(indd)--+-TO(outdd)------------------+-----------> +-DISCARD(savedd)------------+ '-TO(outdd)--DISCARD(savedd)-' .---------------. V | >----+-ON(p,m,f)-+-+--+-ALLDUPS-----+--+-------------+----------> '-ON(VLEN)--' +-NODUPS------+ '-VSAMTYPE(x)-' +-HIGHER(x)---+ +-LOWER(y)----+ +-EQUAL(v)----+ +-FIRST-------+ +-FIRST(u)----+ +-LAST--------+ +-FIRSTDUP----+ +-FIRSTDUP(w)-+ '-LASTDUP-----' >--+-------+--+-------------+---------------------------------->< '-UZERO-' '-USING(xxxx)-' Selects records from an input data set based on meeting criteria for the number of times specified numeric or character field values occur. This makes it possible to only keep records with duplicate field values, only keep records with no duplicate field values, only keep records with field values that occur more than, less than, or exactly n times, only keep the first or first n duplicate records with each field value, or only keep the first or last record with each unique or duplicate field value. From 1 to 10 fields can be specified. At least one ON(VLEN) or ON(p,m,f) field must be specified; all such ON fields specified will be used to determine the "value count" (that is, the number of times the ON values occur) to be matched against the criteria. DISCARD(savedd) can be used to save the records that do not meet the criteria (that is, the discarded records), in the savedd data set. DISCARD(savedd) can be used with or without TO(outdd). DFSORT is called to sort the indd data set. ICETOOL uses its E35 exit to determine which records to include in the outdd data set or savedd data set. ICETOOL passes the EQUALS option to DFSORT to ensure that duplicates are kept in their original input order. The DFSORT control statements in xxxxCNTL are used if USING(xxxx) is specified. Do not supply your own MODS, SUM or OUTREC statement. You can use comment statements. You can use INCLUDE,
OMIT, INREC, OPTION, SORT, or OUTFIL statements providing you observe
these rules:
ICETOOL requires extra storage for SELECT processing, over and above what is normally needed by ICETOOL and DFSORT, in order to save your records until it can determine whether or not they meet your specified criteria. In most cases, only a small amount of storage is needed and can be obtained (above 16MB virtual). However, for a FROM data set with a large record length and criteria requiring many saved records, a large amount of storage is needed. For example, with a record length of 32756 and HIGHER(99), over 3 MBs of storage is needed. If ICETOOL cannot get the storage it needs, it issues a message and terminates the SELECT operation. Increasing the REGION by the amount indicated in the message may allow ICETOOL to run successfully. The DYNALLOC option is passed to DFSORT to ensure that work space
is available for the sort. If your installation defaults for dynamic
allocation are inappropriate for a SELECT operator, you can specify
USING(xxxx) and take one of the following actions:
Tape work data sets cannot be used with ICETOOL. |
Copyright IBM Corporation 1990, 2014
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