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The retrieval commands, FIND, MULTIFIND, and SUBSET, locate
entries in the data base(s) according to data item values in the
entries. You can use retrieval commands to:
Locate entries in a single data set.
Locate entries in multiple data sets.
Locate all entries in one data set or multiple data sets
regardless of the value of the data item specified.
Locate entries in multiple data bases.
Entries must be located before they can be reported, replaced,
or deleted. The located entries remain available for use until QUERY
execution is terminated, the entries are deleted, or until another
FIND, MULTIFIND or JOIN command is entered. This means that located
entries can be listed using one report format and then again using
another format without using the retrieval command again.
A retrieval command consists of one or more relations, each
containing a data item name, relational operator, and one or more
values separated by commas. For example:
>FIND LAST-NAME IS MARTENSEN
USING SERIAL READ
1 ENTRIES QUALIFIED
>
In this example, L-NAME is the item name, IS is the relational
operator, and MARTENSEN is the value. QUERY prints the number of
qualifying entries.
When a retrieval command is executed, QUERY searches the appropriate
data set(s) for the data entries which satisfy the relation(s).
QUERY then stores the record addresses of these entries in a select
file. When a REPORT, REPORT ALL, UPDATE DELETE or UPDATE REPLACE
command is executed, the select file is used to locate the data entries.
A retrieval command can be stored as a procedure in a Proc-file
for repeated use without re-entering the command. Retrieval procedures
can be created which prompt you for the desired search values when
the procedure is executed. This allows you to search for different
values of the same data item each time the procedure is executed.
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