COLLECT.IXVALS

COLLECT.IXVALS is a subroutine used to return a list of all the data values in a particular Btree index.

COLLECT.IXVALS(file_name, index_name)

In returning all data values, COLLECT.IXVALS is different from BTREE.EXTRACT, which returns a list of primary keys associated with one or more specific data values. COLLECT.IXVALS is the basis for the CATALYST "V" call. Because a Btree index is always maintained in sorted order, COLLECT.IXVALS will return a sorted list of data values. This list can in turn be displayed in a popup, used in a report, etc.

Use file_name to pass the name of the data file for which the index lookup is being done.

Use index_name to pass the name of the index (field) for which data values are to be returned.

Data values found by COLLECT.IXVALS are returned in @PSEUDO using @FM as a delimiter. The list of return values is limited to 64K; lists longer than this will be truncated.

DECLARE SUBROUTINE MSG, INPUT.CHAR, FSMSG, COLLECT.IXVALS

/* program to call COLLECT.IXVALS any hits found by 
COLLECT.IXVALS are returned via @PSEUDO using @FM as the 
delimiter */

OPEN "FILES" TO files.file ELSE FSMSG(); STOP

* prompt for file name

LOOP
    error = 0
    file_name = ""
    MSG("Enter file name to fetch index for", "RC", 
file_name, "")
    IF file_name THEN
        READ file.info FROM files.file, file_name ELSE
            MSG(file_name:" not a valid file!","","","")
            error = 1
        END
    END
WHILE error REPEAT

* prompt for an index name
OPEN "DICT.":file_name TO file.dict ELSE
    MSG("Can't open DICT of ":FILE_NAME:"!","","","")
    STOP
END

LOOP
    error = 0
    INDEX_NAME = ""
    MSG("Enter name of index to display", "R", 
index_name,"")
    IF index_name THEN
        * confirm that this is a valid field
        READ confirm FROM file.dict, index_name THEN
            * confirm that this is an indexed field
            confirm = XLATE("!":file_name, "*INDEXES", 1, "X")
            LOCATE index_name IN confirm SETTING POS ELSE
                error = 1
                MSG(INDEX_NAME:" not an index!","","","")
            END ; * LOCATE
        END ELSE
            MSG(index_name:" is an invalid field!","","","")
            error = 1
        END ; * READ confirm
    END
WHILE error REPEAT

@@PSEUDO = ""
COLLECT.IXVALS( file_name, index_name )
IF @PSEUDO THEN
    CONVERT @FM TO @VM IN @PSEUDO
    MSG("COLLECT.IXVALS returned|":@PSEUDO, "", "", "")
END ELSE
    MSG("No values returned for COLLECT.IXVALS", "", "", "")
END
STOP