On OpenVMS an alternative to using the SORT statement within COBOL is to sort at the operating system level, using the bundled SORT utility, which you can access via the SORT, MERGE, and CONVERT DCL commands. <>

On OpenVMS Alpha, you can choose between two sorting methods: Hypersort and SORT-32. SORT-32 is the default. Consult the DCL online help (type $HELP SORT) for details about the two methods, which have effects on optimization and other differences, and information about how to switch between SORT-32 and Hypersort. If you select Hypersort at DCL level, it will be in effect for a SORT statement within a COBOL program as well. <>

On Tru64 UNIX, Hypersort is the sole method available. <>

On OpenVMS VAX, SORT-32 is the sole method available. <>

See Appendix A for the record and key size limits with SORT-32 and Hypersort.

9.2 Merging Data with the MERGE Statement

The MERGE statement combines two or more identically sequenced files and makes their records available, in merged order, to an output procedure or to one or more output files. Use MERGE statement phrases the same way you use their SORT statement phrase equivalents. Note that the SORT phrases with DUPLICATES IN ORDER INPUT PROCEDURE are not allowed with MERGE.

In Example 9-6, district sales data is merged into one regional sales file.

Example 9-6 Using the MERGE Statement

. . . DATA DIVISION. FILE SECTION. SD MERGE-FILE. 01 MERGE-REC. 03 FILLER PIC XX. 03 M-PRODUCT-CODE PIC X(10). 03 FILLER PIC X(88). FD DISTRICT1-SALES. 01 DISTRICT1-REC PIC X(100). FD DISTRICT2-SALES. 01 DISTRICT2-REC PIC X(100). FD REGION1-SALES. 01 REGION1-REC PIC X(100). PROCEDURE DIVISION. 000-MERGE-FILES. MERGE MERGE-FILE ON ASCENDING KEY M-PRODUCT-CODE USING DISTRICT1-SALES DISTRICT2-SALES GIVING REGION1-SALES. STOP RUN.

9.3 Sample Programs Using the SORT and MERGE Statements

The programs in Example 9_7 , Example 9_8 , Example 9-9 , Example 9_10 , Example 9_11 , and Example 9-12 all show how to use the SORT and MERGE statements.

Example 9-7 shows how to use the SORT statement with the USING and GIVING phrases.

Example 9-7 Sorting a File with the USING and GIVING Phrases

IDENTIFICATION DIVISION. PROGRAM-ID. SORTA. ************************************************* * This program shows how to sort * * a file with the USING and GIVING phrases * * of the SORT statement. The fields to be * * sorted are S-KEY-1 and S-KEY-2; they * * contain account numbers and amounts. The * * sort sequence is amount within account * * number. * * Notice that OUTPUT-FILE is a relative file. * ************************************************* ENVIRONMENT DIVISION. CONFIGURATION SECTION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT INPUT-FILE ASSIGN TO "INPFIL". SELECT OUTPUT-FILE ASSIGN TO "OUTFIL" ORGANIZATION IS RELATIVE. SELECT SORT-FILE ASSIGN TO "SRTFIL". DATA DIVISION. FILE SECTION. SD SORT-FILE. 01 SORT-REC. 03 S-KEY-1. 05 S-ACCOUNT-NUM PIC X(8). 03 FILLER PIC X(32). 03 S-KEY-2. 05 S-AMOUNT PIC S9(5)V99. 03 FILLER PIC X(53). FD INPUT-FILE LABEL RECORDS ARE STANDARD. 01 IN-REC PIC X(100). FD OUTPUT-FILE LABEL RECORDS ARE STANDARD. 01 OUT-REC PIC X(100). PROCEDURE DIVISION. 000-DO-THE-SORT. SORT SORT-FILE ON ASCENDING KEY S-KEY-1 S-KEY-2 WITH DUPLICATES IN ORDER USING INPUT-FILE GIVING OUTPUT-FILE. *********************************************************** * At this point, you could transfer control to another * * section of your program and continue processing. * *********************************************************** DISPLAY "END OF PROGRAM SORTA". STOP RUN.

Example 9-8 shows how to use the USING and OUTPUT PROCEDURE phrases.

Example 9-8 Using the USING and OUTPUT PROCEDURE Phrases

IDENTIFICATION DIVISION. PROGRAM-ID. SORTB. ************************************************************** * This program shows how to sort a file * * with the USING and OUTPUT PROCEDURE phrases * * of the SORT statement. The program eliminates * * duplicate records by adding their amounts to the * * amount in the first record with the same account * * number. Only records with unique account numbers * * are written to the output file. The fields to be * * sorted are S-KEY-1 and S-KEY-2; they contain account * * numbers and amounts. The sort sequence is amount * * within account number. * * Notice that the organization of OUTPUT-FILE is indexed. * ************************************************************** ENVIRONMENT DIVISION. CONFIGURATION SECTION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT INPUT-FILE ASSIGN TO "INPFIL". SELECT OUTPUT-FILE ASSIGN TO "OUTFIL" ORGANIZATION IS INDEXED. SELECT SORT-FILE ASSIGN TO "SRTFIL". DATA DIVISION. FILE SECTION. SD SORT-FILE. 01 SORT-REC. 03 S-KEY-1. 05 S-ACCOUNT-NUM PIC X(8). 03 FILLER PIC X(32). 03 S-KEY-2. 05 S-AMOUNT PIC S9(5)V99. 03 FILLER PIC X(53). FD INPUT-FILE LABEL RECORDS ARE STANDARD. 01 IN-REC PIC X(100). FD OUTPUT-FILE LABEL RECORDS ARE STANDARD ACCESS MODE IS SEQUENTIAL RECORD KEY IS OUT-KEY. 01 OUT-REC. 03 OUT-KEY PIC X(8). 03 FILLER PIC X(92). WORKING-STORAGE SECTION. 01 INITIAL-SORT-READ PIC X VALUE "Y". 01 SAVE-SORT-REC. 03 SR-ACCOUNT-NUM PIC X(8). 03 FILLER PIC X(32). 03 SR-AMOUNT PIC S9(5)V99. 03 FILLER PIC X(53). PROCEDURE DIVISION. 000-START SECTION. 005-DO-THE-SORT. SORT SORT-FILE ON ASCENDING KEY S-KEY-1 S-KEY-2 USING INPUT-FILE OUTPUT PROCEDURE IS 300-CREATE-OUTPUT-FILE THRU 600-DONE-CREATE. ************************************************************ * At this point, you could transfer control to another * * section of the program and continue processing. * ************************************************************ DISPLAY "END OF PROGRAM SORTB". STOP RUN. 300-CREATE-OUTPUT-FILE SECTION. 350-OPEN-OUTPUT. OPEN OUTPUT OUTPUT-FILE. 400-READ-SORT-FILE. RETURN SORT-FILE AT END PERFORM 500-WRITE-THE-OUTPUT CLOSE OUTPUT-FILE GO TO 600-DONE-CREATE. IF INITIAL-SORT-READ = "Y" MOVE SORT-REC TO SAVE-SORT-REC MOVE "N" TO INITIAL-SORT-READ GO TO 400-READ-SORT-FILE. 450-COMPARE-ACCOUNT-NUM. IF S-ACCOUNT-NUM = SR-ACCOUNT-NUM ADD S-AMOUNT TO SR-AMOUNT GO TO 400-READ-SORT-FILE. 500-WRITE-THE-OUTPUT. MOVE SAVE-SORT-REC TO OUT-REC. WRITE OUT-REC INVALID KEY DISPLAY "INVALID KEY " SR-ACCOUNT-NUM " SORTB ABORTED" CLOSE OUTPUT-FILE STOP RUN. 550-GET-A-REC. MOVE SORT-REC TO SAVE-SORT-REC. GO TO 400-READ-SORT-FILE. 600-DONE-CREATE SECTION. 650-EXIT-PARAGRAPH. EXIT.

Example 9-9 shows how to use the INPUT PROCEDURE and OUTPUT PROCEDURE phrases.

Example 9-9 Using the INPUT PROCEDURE and OUTPUT PROCEDURE Phrases

IDENTIFICATION DIVISION. PROGRAM-ID. SORTC. ********************************************************* * This program shows how to use the INPUT * * PROCEDURE and OUTPUT PROCEDURE phrases of the * * SORT statement. Input to the sort is two files * * containing the same type of data. Records with * * a "D" status-code are not released to the sort. * * The program eliminates duplicate records by * * adding their amounts to the amount in the first * * record with the same account number. Only records * * with unique account numbers are written to * * the output file. The fields to be sorted are * * S-KEY-1 and S-KEY-2. The sort sequence is amount * * within account number. * ********************************************************* ENVIRONMENT DIVISION. CONFIGURATION SECTION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT FIRST-FILE ASSIGN TO "FILE01". SELECT SECOND-FILE ASSIGN TO "FILE02". SELECT OUTPUT-FILE ASSIGN TO "OUTFIL". SELECT SORT-FILE ASSIGN TO "SRTFIL". DATA DIVISION. FILE SECTION. SD SORT-FILE. 01 SORT-REC. 03 S-KEY-1. 05 S-ACCOUNT-NUM PIC X(8). 03 FILLER PIC X(32). 03 S-KEY-2. 05 S-AMOUNT PIC S9(5)V99. 03 FILLER PIC X(53). FD FIRST-FILE LABEL RECORDS ARE STANDARD. 01 RECORD1. 03 FILLER PIC X(99). 03 R1-STATUS-CODE PIC X. FD SECOND-FILE LABEL RECORDS ARE STANDARD. 01 RECORD2. 03 FILLER PIC X(99). 03 R2-STATUS-CODE PIC X. FD OUTPUT-FILE LABEL RECORDS ARE STANDARD. 01 OUT-REC PIC X(100). WORKING-STORAGE SECTION. 01 INITIAL-SORT-READ PIC X VALUE "Y". 01 FILE01-COUNT PIC 9(5) VALUE ZEROES. 01 FILE02-COUNT PIC 9(5) VALUE ZEROES. 01 SORT-COUNT PIC 9(5) VALUE ZEROES. 01 OUTPUT-COUNT PIC 9(5) VALUE ZEROES. 01 SAVE-SORT-REC. 03 SR-ACCOUNT-NUM PIC X(8). 03 FILLER PIC X(32). 03 SR-AMOUNT PIC S9(5)V99. 03 FILLER PIC X(53). PROCEDURE DIVISION. 000-START SECTION. 005-DO-THE-SORT. SORT SORT-FILE ON ASCENDING KEY S-KEY-1 S-KEY-2 INPUT PROCEDURE IS 010-GET-INPUT THRU 200-DONE-INPUT-GET OUTPUT PROCEDURE IS 300-CREATE-OUTPUT-FILE THRU 600-DONE-CREATE. ******************************************************** * Notice the use of DISPLAY and record counters to * * produce sort statistics. * ******************************************************** DISPLAY "TOTAL FIRST-FILE RECORDS IS " FILE01-COUNT. DISPLAY "TOTAL SECOND-FILE RECORDS IS " FILE02-COUNT. DISPLAY "TOTAL NUMBER OF SORTED RECORDS IS " SORT-COUNT. DISPLAY "TOTAL NUMBER OF OUTPUT RECORDS IS " OUTPUT-COUNT. ************************************************************ * At this point, you could transfer control to another * * section of the program and continue processing. * ************************************************************ DISPLAY "END OF PROGRAM SORTC". STOP RUN. 010-GET-INPUT SECTION. 050-OPEN-FILES. OPEN INPUT FIRST-FILE. 100-READ-FIRST-FILE. READ FIRST-FILE AT END CLOSE FIRST-FILE OPEN INPUT SECOND-FILE GO TO 150-READ-SECOND-FILE. ADD 1 TO FILE01-COUNT. IF R1-STATUS-CODE = "D" GO TO 100-READ-FIRST-FILE. RELEASE SORT-REC FROM RECORD1. GO TO 100-READ-FIRST-FILE. 150-READ-SECOND-FILE. READ SECOND-FILE AT END CLOSE SECOND-FILE GO TO 200-DONE-INPUT-GET. ADD 1 TO FILE02-COUNT. IF R2-STATUS-CODE = "D" GO TO 150-READ-SECOND-FILE. RELEASE SORT-REC FROM RECORD2. GO TO 150-READ-SECOND-FILE. 200-DONE-INPUT-GET SECTION. 250-EXIT-PARAGRAPH. EXIT. 300-CREATE-OUTPUT-FILE SECTION. 350-OPEN-OUTPUT. OPEN OUTPUT OUTPUT-FILE. 400-READ-SORT-FILE. RETURN SORT-FILE AT END PERFORM 500-WRITE-THE-OUTPUT CLOSE OUTPUT-FILE GO TO 600-DONE-CREATE. ADD 1 TO SORT-COUNT. IF INITIAL-SORT-READ = "Y" MOVE SORT-REC TO SAVE-SORT-REC MOVE "N" TO INITIAL-SORT-READ GO TO 400-READ-SORT-FILE. 450-COMPARE-ACCOUNT-NUM. IF S-ACCOUNT-NUM = SR-ACCOUNT-NUM ADD S-AMOUNT TO SR-AMOUNT GO TO 400-READ-SORT-FILE. 500-WRITE-THE-OUTPUT. MOVE SAVE-SORT-REC TO OUT-REC. WRITE OUT-REC. ADD 1 TO OUTPUT-COUNT. 550-GET-A-REC. MOVE SORT-REC TO SAVE-SORT-REC. GO TO 400-READ-SORT-FILE. 600-DONE-CREATE SECTION. 650-EXIT-PARAGRAPH. EXIT.

Example 9-10 shows how to use the COLLATING SEQUENCE IS phrase.

Example 9-10 Using the COLLATING SEQUENCE IS Phrase

IDENTIFICATION DIVISION. PROGRAM-ID. SORTD. ************************************************** * This program sorts a file into a non-ASCII * * collating sequence. The collating sequence * * is defined by the alphabet-name MYSEQUENCE * * in the SPECIAL-NAMES paragraph of the * * ENVIRONMENT DIVISION. * * The collating sequence is: * * 1. The letters A to Z * * 2. The digits 0 to 9 * ************************************************** ENVIRONMENT DIVISION. CONFIGURATION SECTION. SPECIAL-NAMES. ALPHABET MYSEQUENCE IS "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 ". INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT INPUT-FILE ASSIGN TO "INPFIL". SELECT OUTPUT-FILE ASSIGN TO "OUTFIL". SELECT SORT-FILE ASSIGN TO "SRTFIL". DATA DIVISION. FILE SECTION. SD SORT-FILE. 01 SORT-REC. 03 S-KEY-1. 05 S-ACCOUNT-NAME PIC X(23). 03 S-KEY-2. 05 S-AMOUNT PIC S9(5)V99. FD INPUT-FILE LABEL RECORDS ARE STANDARD. 01 IN-REC PIC X(30). FD OUTPUT-FILE LABEL RECORDS ARE STANDARD. 01 OUT-REC PIC X(30). PROCEDURE DIVISION. 000-DO-THE-SORT. SORT SORT-FILE ON ASCENDING KEY S-KEY-1 S-KEY-2 COLLATING SEQUENCE IS MYSEQUENCE USING INPUT-FILE GIVING OUTPUT-FILE. ************************************************************ * At this point, you could transfer control to another * * section of the program and continue processing. * ************************************************************ DISPLAY "END OF PROGRAM SORTD". STOP RUN.

Example 9-11 is an example of creating a new sort key.

Example 9-11 Creating a New Sort Key

IDENTIFICATION DIVISION. PROGRAM-ID. SORTE. ************************************************ * This program increases the size of the * * variable input records by a new six- * * character field and uses this field * * as the sort key. * ************************************************ ENVIRONMENT DIVISION. CONFIGURATION SECTION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT INFILE ASSIGN TO "INFILE". SELECT SORT-FILE ASSIGN TO "SRTFIL". SELECT OUT-FILE ASSIGN TO "OUTFILE". DATA DIVISION. FILE SECTION. FD INFILE RECORD VARYING FROM 100 TO 490 CHARACTERS DEPENDING ON IN-LENGTH. 01 INREC. 03 ACCOUNT PIC 9(5). 03 INCOME-FIRST-QUARTER PIC 9(5)V99. 03 INCOME-SECOND-QUARTER PIC 9(5)V99. 03 INCOME-THIRD-QUARTER PIC 9(5)V99. 03 INCOME-FOURTH-QUARTER PIC 9(5)V99. 03 ORDER-COUNT PIC 9(2). 03 ORDERS OCCURS 1 TO 7 TIMES DEPENDING ON ORDER-COUNT. 05 ORDER-DATE PIC 9(6). 05 FILLER PIC X(59). SD SORT-FILE RECORD VARYING FROM 106 TO 496 CHARACTERS DEPENDING ON SORT-LENGTH. 01 SORT-REC. 03 SORT-ANNUAL-INCOME PIC 9(6). 03 SORT-REST-OF-RECORD PIC X(490). FD OUT-FILE RECORD VARYING FROM 106 TO 496 CHARACTERS DEPENDING ON OUT-LENGTH. 01 OUT-REC PIC X(496). WORKING-STORAGE SECTION. 01 IN-LENGTH PIC 9(3) COMP. 01 SORT-LENGTH PIC 9(3) COMP. 01 OUT-LENGTH PIC 9(3) COMP. PROCEDURE DIVISION. 000-START SECTION. 005-SORT-HERE. SORT SORT-FILE ON DESCENDING SORT-ANNUAL-INCOME INPUT PROCEDURE 010-GET-INPUT THRU 070-DONE-INPUT OUTPUT PROCEDURE 100-WRITE-OUTPUT. DISPLAY "END OF PROGRAM SORTE". STOP RUN. 010-GET-INPUT SECTION. 020-OPEN-INPUT. OPEN INPUT INFILE. 030-READ-INPUT. READ INFILE AT END CLOSE INFILE GO TO 070-DONE-INPUT. 040-ADD-INCOME. ADD INCOME-FIRST-QUARTER INCOME-SECOND-QUARTER INCOME-THIRD-QUARTER INCOME-FOURTH-QUARTER GIVING SORT-ANNUAL-INCOME. 050-CREATE-SORT-REC. ADD 6 IN-LENGTH GIVING SORT-LENGTH. MOVE INREC TO SORT-REST-OF-RECORD. RELEASE SORT-REC. GO TO 030-READ-INPUT. 070-DONE-INPUT SECTION. 080-EXIT. EXIT. 100-WRITE-OUTPUT SECTION. 110-OPEN. OPEN OUTPUT OUT-FILE. 120-WRITE. RETURN SORT-FILE AT END CLOSE OUT-FILE GO TO 130-DONE. MOVE SORT-LENGTH TO OUT-LENGTH. WRITE OUT-REC. GO TO 120-WRITE. 130-DONE. EXIT.

Example 9-12 merges three identically sequenced files into one file.

Example 9-12 Merging Files

IDENTIFICATION DIVISION. PROGRAM-ID. MERGE01. ****************************************************** * This program merges three identically sequenced * * regional sales files into one total sales file. * * The program adds sales amounts and writes one * * record for each product code. * ****************************************************** ENVIRONMENT DIVISION. CONFIGURATION SECTION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT REGION1-SALES ASSIGN TO "REG1SLS". SELECT REGION2-SALES ASSIGN TO "REG2SLS". SELECT REGION3-SALES ASSIGN TO "REG3SLS". SELECT MERGE-FILE ASSIGN TO "MRGFILE". SELECT TOTAL-SALES ASSIGN TO "TOTLSLS". DATA DIVISION. FILE SECTION. FD REGION1-SALES LABEL RECORDS ARE STANDARD. 01 REGION1-RECORD PIC X(100). FD REGION2-SALES LABEL RECORDS ARE STANDARD. 01 REGION2-RECORD PIC X(100). FD REGION3-SALES LABEL RECORDS ARE STANDARD. 01 REGION3-RECORD PIC X(100). SD MERGE-FILE. 01 MERGE-REC. 03 M-REGION-CODE PIC XX. 03 M-PRODUCT-CODE PIC X(10). 03 M-SALES-AMT PIC S9(7)V99. 03 FILLER PIC X(79). FD TOTAL-SALES LABEL RECORDS ARE STANDARD. 01 TOTAL-RECORD PIC X(100). WORKING-STORAGE SECTION. 01 INITIAL-READ PIC X VALUE "Y". 01 THE-COUNTERS. 03 PRODUCT-AMT PIC S9(7)V99. 03 REGION1-AMT PIC S9(9)V99. 03 REGION2-AMT PIC S9(9)V99. 03 REGION3-AMT PIC S9(9)V99. 03 TOTAL-AMT PIC S9(11)V99. 01 SAVE-MERGE-REC. 03 S-REGION-CODE PIC XX. 03 S-PRODUCT-CODE PIC X(10). 03 S-SALES-AMT PIC S9(7)V99. 03 FILLER PIC X(79). PROCEDURE DIVISION. 000-START SECTION. 010-MERGE-FILES. OPEN OUTPUT TOTAL-SALES. MERGE MERGE-FILE ON ASCENDING KEY M-PRODUCT-CODE USING REGION1-SALES REGION2-SALES REGION3-SALES OUTPUT PROCEDURE IS 020-BUILD-TOTAL-SALES THRU 100-DONE-TOTAL-SALES. DISPLAY "TOTAL SALES FOR REGION 1 " REGION1-AMT. DISPLAY "TOTAL SALES FOR REGION 2 " REGION2-AMT. DISPLAY "TOTAL SALES FOR REGION 3 " REGION3-AMT. DISPLAY "TOTAL ALL SALES " TOTAL-AMT. CLOSE TOTAL-SALES. DISPLAY "END OF PROGRAM MERGE01". STOP RUN. 020-BUILD-TOTAL-SALES SECTION. 030-GET-MERGE-RECORDS. RETURN MERGE-FILE AT END MOVE PRODUCT-AMT TO S-SALES-AMT WRITE TOTAL-RECORD FROM SAVE-MERGE-REC GO TO 100-DONE-TOTAL-SALES. IF INITIAL-READ = "Y" MOVE "N" TO INITIAL-READ MOVE MERGE-REC TO SAVE-MERGE-REC PERFORM 050-TALLY-AMOUNTS GO TO 030-GET-MERGE-RECORDS. 040-COMPARE-PRODUCT-CODE. IF M-PRODUCT-CODE = S-PRODUCT-CODE PERFORM 050-TALLY-AMOUNTS GO TO 030-GET-MERGE-RECORDS. MOVE PRODUCT-AMT TO S-SALES-AMT. MOVE ZEROES TO PRODUCT-AMT. WRITE TOTAL-RECORD FROM SAVE-MERGE-REC. MOVE MERGE-REC TO SAVE-MERGE-REC. GO TO 040-COMPARE-PRODUCT-CODE. 050-TALLY-AMOUNTS. ADD M-SALES-AMT TO PRODUCT-AMT TOTAL-AMT. IF M-REGION-CODE = "01" ADD M-SALES-AMT TO REGION1-AMT. IF M-REGION-CODE = "02" ADD M-SALES-AMT TO REGION2-AMT. IF M-REGION-CODE = "03" ADD M-SALES-AMT TO REGION3-AMT. 100-DONE-TOTAL-SALES SECTION. 120-DONE. EXIT.