AS/400 or IBM i-series or System i Application System/400 Layered machine architecture Distributed Processing Object orientation Single-level storage Hierarchy of microprocessors Security levels OPERATING SYSTEM Operating system used in AS/400 is OS400 Object-Based Programming Languages - RPG400, CL400, Cobol400, Java 400, SQL 400, etc. SECURITY Various Security provided by the system No security Password security Resource security OS security C2 level security LIBRARY A library is a system object that serves as a directory to other objects. Libraries provide a method for organizing objects. Libraries themselves are objects. CRTLIB command is used to create a library. LIBRARY LIST System library- 15 (QSYSLIB) ± QSYS ± QHLPSYS ± QUSRSYS Product library 2 Current library 1 User library - 25 (QUSRLIB) ± QGPL ± QTEMP JOB There are two types of jobs ± Interactive jobs ± Batch jobs How batch Job works? Submit the job Job enters the job queue Job enters the subsystem The memory pool allocates memory to the subsystem The job finishes and moves to the output queue COMMANDS WRKACTJOB Used to find jobs in the system WRKSBMJOB Used to work with the Batch jobs DSPJOB Used to display the job CHGJOBD, DLTJOBD, DSPJOBD, WRKJOBD used to Change, Delete, Display, Work with Job Description DATABASE DATABASE FILES Source File Physical File Logical File NAMING CONVENTIONS file name, record format name, and field name can be as long as 10 characters Field names must be unique in a record format Record format names and member names must be unique in a file File names must be unique in a library CREATING AND DESCRIBING DATABASE FILES Different ways of creating Database file Interactive data definition utility (IDDU) Control Language (CL) Structured Query Language (SQL) i-series navigator SOURCE FILE Source physical file is a file, which has one, or more files included in it. It is just like a directory and it contains many members. CRTSRCPF command is used to create a source file PHYSICAL FILE A physical file contains one record format and one or more members. It s type PF. Maximum number of fields -> 8000. Maximum no of key fields -> 120. CRTPF command is used to create physical file. LEVELS OF ENTRIES IN PHYSICAL FILE There are four levels of entries. File level entries (optional) UNIQUE, LIFO, FIFO, FCFO, REF Record format level entries FORMAT Example: FORMAT (LIB-NAME / FILE-NAME) TEXT Example: TEXT ( description ) LEVELS OF ENTRIES IN PHYSICAL FILE Field level entries CHECK, COLHDG, DATFMT, REFFLD, VALUES, VARLEN, etc. Key field level entries DESCEND, SIGNED, ABSVAL, UNSIGNED, ZONE, etc. VALID DATA TYPES A P S B F H L T Z Character Packed decimal Zoned decimal Binary Floating point Hexadecimal Date Time Timestamp // physical filename : CUSTOMER 0001.00 0002.00 0003.00 0004.00 0005.00 0006.00 A UNIQUE A R RCUST A CUSNO 5S 0 TEXT( CUSTOMER NO ) A CUSNM 30A A CUSAD 30A A K CUSNO ****************** End of data ******************** LOGICAL FILE One or more logical file can be derived from a single physical file. A logical file can contain up to 32 record formats. It cannot exist without a physical file. Type is LF. CRTLF command is used to create a Logical file. TYPES OF LOGICAL FILE Non-Join logical file Join logical file LEVELS OF ENTRIES IN LOGICAL FILE There are six levels of entries. File level entries (optional) ± JDFTVAL, DYNSLT, etc Record format level entries ± JFILE Field level entries (Optional) ± JREF, ALL, CONCAT, RENAME, SST Key field level entries (Optional) JOIN Level entries ± JOIN, JFLD, JDUPSEQ Select / Omit level entries (Optional) LEVELS OF ENTRIES IN LOGICAL FILE JOIN Level entries It is not applicable to NON JOIN LOGICAL FILES Select / Omit level entries // Logical filename : example1 *************** Beginning of data ********************* 0001.00 R RECSEL PFILE (EXAMPLE) 0002.00 K EMPNO 0003.00 S EMPNO CMP (GT 10003) 0004.00 O EMPNAME CMP (EQ 'SHYAM') ****************** End of data ************************** // Logical filename : example2 *************** Beginning of data ************************** 0001.00 R EMP JFILE (SAMPLE SAMPLE) 0002.00 J JOIN (1 2) 0003.00 JFLD (MGRID EMPID) 0004.00 EMPID JREF (1) 0005.00 EMPNAME JREF (1) 0006.00 MANAGER RENAME (EMPNAME) JREF (2) 0007.00 COLHDG ('MANAGER') ****************** End of data ***************************** COMMANDS 1. DSPFFD used for listing details about individual fields. 2. DSPFD used to display the details about the file when it is created. 3. DSPDBR used to list all the files, which are related to a PF. 4. DSPOBJD used to know library name, object name and the source PF where it is residing. ACCESS PATH An access path describes how records in a database file are retrieved Types of Access Path ± Arrival Sequence Access Path ± Keyed Sequence Access Path OPEN QUERY FILE It acts as a filter between the processing program and the database records. OPNQRYF command creates only a temporary file for processing the data. The typical use of the OPNQRYF command is to select, arrange, and format the data. STEPS FOR CREATING OPNQRYF override database file ± OVRDBF FILE (file PF) TOFILE (LIB/ PF) SHARE (*Yes) Query selection ± OPNQRYF FILE (LIB / PF) QRYSLT ( EMPNO *EQ*BCAT &A ) Calling RPG program ± CALL PGM (LIB/NAME) PARM () Delete override ± DLTOVR FILE (OPNPF) Closing the file ± CLOF OPNID (OPNPF) LOCK It helps to give the access permission for database file. Types of lock Share lock Exclusive lock CONTROL LANGUAGE (CL) CONTROL LANGUAGE Control language (CL) is the primary interface to the operating system. CL can be used at the same time by users at different workstations, in batch and interactive jobs and in CL programs and procedures CL PROGRAMS & PROCEDURE CL programs and procedures are created from source statements that consist entirely of CL commands Using CL programs and procedures is faster than entering and running the commands individually CL programs and procedures provide consistent processing of the same set of commands Parameters can be passed to CL programs and procedures TYPES OF CL PROGRAMS AND PROCEDURES CL procedure ± It is a set of statements that performs a particular task and then returns to the caller. CL module ± It is the object that results from compiling highlevel language source statements using an Integrated Language Environment (ILE) compiler. TYPES OF CL PROGRAMS AND PROCEDURES CL program ± It is a program that is created from source statements consisting entirely of CL commands. Service program ± A service program is an object that contains one or more modules. PARAMETERS IN CL Parameter is a value that is passed to a command or program to provide user input or control the actions of the command or program Parameter can be a single value or a list of values. PARAMETER SPECIFICATION Keyword form: ± DCL VAR(&QTY) TYPE(*DEC) LEN(5) VALUE(0) Positional form: ± DCL &QTY *DEC 5 0 Positional and keyword forms together: ± DCL &QTY *DEC VALUE(0) EXPRESSIONS IN CL COMMANDS Types of expressions supported in CL programs ± Arithmetic (&VAR + 15) +,- ,*,/ ± Character string (SIX || TEEN) *CAT,*BCAT,*TCAT ± Relational (&VAR > 15) =, >, <, >=, <=, *EQ, *GT, *LT, *GE, *LE, *NE,etc. ± Logical (&VAR *OR &TEST) *AND,*OR,*NOT,&,|,¬ SAMPLE CL PROGRAM // SAMP9CL PGM DCL VAR(&CHOICE) TYPE(*DEC) LEN(1) DCLF FILE(SAMP9) TOP: SNDRCVF RCDFMT(MAINMENU) IF COND(&CHOICE *EQ 5) THEN(GOTO CMDLBL(EXIT)) /* CALL THE ADDITION PROGRAM*/ IF COND(&CHOICE *EQ 1) THEN(DO) CALL PGM(SAMP9ADD) ENDDO GOTO CMDLBL(TOP) EXIT: Endpgm //SAMP9ADD CL FILE PGM DCL VAR(&NUM1) TYPE(*DEC) LEN(4) DCL VAR(&NUM2) TYPE(*DEC) LEN(4) DCLF FILE(SAMP9) RCDFMT(ADDITION) SNDRCVF RCDFMT(ADDITION) CHGVAR VAR(&SUM) VALUE(&NUM1 + &NUM2) SNDRCVF RCDFMT(ADDITION) Endpgm DATA AREA A data area is an object used to store data for access by any job running on the system. It is permanent storage It is of limited size and independent of the existence of the programs or files Data area created by the system 1. Local Data Area 2. Group Data Area LOCAL DATA AREA A local data area is created for each job in the system automatically, when a job is submitted. Only One Data Area is created when a job is submitted initially filled with blanks, with a length of 1024 and type *CHAR. No library is associated with the local data area. GROUP DATA AREA System creates a group data area when an interactive job becomes a group job. Only one group data area can exist for a group Initially filled with blanks, has a length of 512 and type *CHAR. No library is associated with a group data area. COMMANDS CRTDTAARA Used to create a general data area RTVDTAARA Used to retrieve values from data area. CHGDTAARA Used to change the value of data area DSPDTAARA Used to display the current value of data area DLTDTAARA Used to delete a data area COMMANDS Accessing Local Data Area ± CHGVAR VAR (%SST (*LDA 3 5)) VALUE(123) ± RTVDTAARA DTAARA (*LDA (3 5)) RTNVAR (&ROLNO) Accessing Group Data Area ± CHGDTAARA DTAARA (*GDA) VALUE ( DECEMBER 1996 ) ± RTVDTAARA DTAARA (*GDA) RTNVAR (&GRPARA) SAMPLE PROGRAM PGM CRTDTAARA DTAARA(MYLIB/DA1) TYPE(*CHAR) LEN(5) VALUE(ABCDE) . . . DCL VAR(&CLVAR1) TYPE(*CHAR) LEN(3) RTVDTAARA DTAARA(MYLIB/DA1 (3 3)) RTNVAR(&CLVAR1) ENDPGM MESSAGE Message is the interface between operating system and the programs or user and program. Immediate message Predefined message Monitor message(MONMSG) IMMEDIATE MESSAGE Immediate messages are created by the program or system user when they are sent and are not permanently stored in the system. ± SNDUSRMSG, SNDBRKMSG, SNDMSG Ex: SNDUSRMSG HELLO PREDEFINED MESSAGE Predefined messages are created before they are used. These messages are placed in a message file (queue) when they are created, and retrieved from the file when they are used. MONMSG The monitor message (MONMSG) command monitors the message send to the program message queue for the conditions specified in the command. If condition exists, the CL command specified on the MONMSG command is run. ± Ex: MONMSG MSGID (MCH1211) CMPDTA (LIB) Two levels of MONMSG command ± Program level ± Specific command level PROGRAM LEVEL MONMSG: PGM PARM(&CALLER &PGM) DCL VAR(&CALLER) TYPE(*CHAR) LEN(10) DCL VAR(&PGM) TYPE(*CHAR) LEN(10) DCL VAR(&MSGKEY) TYPE(*CHAR) LEN(4) DCL VAR(&SENDER) TYPE(*CHAR) LEN(80) MONMSG MSGID(CPF0000) EXEC(GOTO CMDLBL(ERROR)) ERROR: CHGVAR VAR(&CALLER) VALUE(' ') ENDPGM SPECIFIC COMMAND LEVEL MONMSG: PGM MONMSG MSGID(CPF0001) EXEC(GOTO ERROR) CALL PROGA CALL PROGB RETURN ERROR: SNDPGMMSG MSG( A CALL command failed ) MSGTYPE(*ESCAPE) ENDPGM COMMANDS SNDUSRMSG - Send a message to a user SNDPGMMSG - Send a message to a message queue SNDBRKMSG - Send Break Message REPORT PROGRAM GENERATOR(RPG) DISADVANTAGES OF CL OVER RPG Records can be read but can t able to write or update or delete records. Only one file can be used in a CL program Printer files can t be used in CL Subfile can t be used in a CL program RPG SPECIFICATIONS Seven kinds of specifications are 1. Control specifications 2. File description specifications 3. Extension specifications 4. Line counter specifications 5. Input specifications 6. Calculation specifications 7. Output specifications. CONTROL SPECIFICATION The control specification provides the RPG/400 compiler with information about your program and your system. This includes: 1. Name of the program 2. Date format for the program 3. If an alternative collating sequence or file translation is used. Control Specification is optional FILE DESCRIPTION SPECIFICATION File description specifications describe all the files that your program uses. The information for each file includes: 1. 2. 3. 4. Name of the file How the file is used Size of records in the file Input or output device used for the file EXTENSION SPECIFICATIONS Extension specifications describe all record address files, table files, and array files used in the program. The information includes: 1. 2. 3. 4. Name of the file, table, or array Number of entries in a table or array input record Number of entries in a table or array Length of the table or array entry. LINE COUNTER SPECIFICATIONS Line counter specifications describe the page or form on which output is printed. The information includes: 1. Number of lines per page 2. Line of the page where overflow occurs. INPUT SPECIFICATIONS Input specifications describe the records, fields, data structures and named constants used by the program The information in the input specifications includes: ± ± ± ± Name of the file Sequence of record types Name and Type of each field in the record Named constants. CALCULATION SPECIFICATIONS Calculation specifications describe the calculations to be done on the data and the order of the calculations. The information includes: 1. Control-level and conditioning indicators for the operation specified 2. Fields or constants to be used in the operation OUTPUT SPECIFICATIONS Output specifications describe the records and fields in the output files and the conditions under which output operations are processed. The information includes ± Name of the file ± Spacing instructions for Printer files ± Name and location of each field in output record Entry H F D I C O P Specification Type Control File description Definition Input Calculation Output Procedure ARRAY Array is a collection of data of similar data type and length. Types of arrays ± Run Time Array ± Compile Time Array ± Pre run Time Array RUN TIME ARRAY It is loaded by the program while it is running The values will be dynamic Keywords like ALT, CTDATA, EXTFMT, FROMFILE, PERRCD, and TOFILE cannot be used for a run-time array //Example code *************** Beginning of data *********** c*runtime array darr1 s 10 dim(12) di s 2p 0 inz(1) da s 3p 0 dj s 2p 0 inz(1) c i do 12 c eval arr1(i)=a c dsply arr1(i) c add 1 i c enddo c seton lr ****************** End of data ************** COMPILE TIME ARRAY It is loaded when your program is created. The initial data becomes a permanent part of your program. The value will be static The array data will be present after the last instruction of the RPG program //Example code *************** Beginning of data****************** c*compile time array darr1 s4 dim(3) ctdata perrcd(1) di s 2p 0 inz(1) c i do 3 c arr1(i) dsply c add 1 i c enddo c eval *InLr = *On **ctdata arr1 1001 20 1000 ****************** End of data ******************** PRE RUN TIME ARRAY It is loaded from an array file when your program begins running, before any input, calculation, or output operations are processed The data will be present in a file and using pre-run time array we can retrieve the data. //Example DARE D DARH D D C eval S 5A DIM(250) PERRCD(12) ASCEND FROMFILE(DISKIN) S 5A DIM(250) PERRCD(12) ASCEND FROMFILE(DISKOUT) TOFILE(DISKOUT) *InLr = *On OPCODE ADD (Add) ± C ADD 1 RECNO ADDDUR (Add Duration) ± C ADDDUR YY:*MONTHS DUEDATE DIV (Divide) ± C FACT1 DIV FACT2 RESULT EVAL (Evaluate Expression) ± C EVAL EMPNO = 5001 MULT (Multiply) ±C FACT1 MULT FACT2 RESULT OPCODE MVR (Move remainder) ±C FACT1 MVR FACT2 RESULT SUB (Subtract) ±C SUB 1 RECNO SUBDUR (Subtract Duration) ±C SUBDUR YY:*MONTHS LOANDATE Z-ADD (Zero and Add) ±C Z-ADD 1 SCR1 Z-SUB (Zero and Subtract) ±C Z-SUB 1 SCR1 READ RELATED OPCODE READ (Read a Record) ±C READ FILEA READC (Read Next Changed Record) ±C READC SFCUSR READE (Read Equal Key) ±C KEYFLD READE FILEA READP (Read Prior Record) ±C READP FILEA READPE (Read Prior Equal) ±C FieldA READPE FileA READ RELATED OPCODE CHAIN (Random Retrieval From a File) ± C DEMPNO CHAIN EMPDTLPF IN (Retrieves Data Area) OUT (Write a data area) C *DTAARA DEFINE DATA1 S C *LOCK IN S C EVAL S=G C OUT S SETGT (Set Greater Than) ±C KEY SETGT FILEA SETLL (Set Lower Limit) ± C ORDER SETLL ORDFIL WRITE,UPDATE, DELETE OPCODE DELETE (Delete record) ± C Delete EMPDT UPDATE (Modify Existing Record) ± CUPDATERECFMT WRITE (Create New Records) ± C WRITE FILE1 CONDITION BASED OPCODE DO(do),DOU(Do Until),DOW(Do While) end with ENDDO (ending do) C DO 10 C FLDA DOUEQ FLDB C ENDDO C ENDDO FOR (For) will end with ENDFOR (end for) C for i = 1 to n C Eval factorial = factorial * i C endfor GOTO (Go To) ± C GOTO END CONDITION BASED OPCODE IF(If) ELSEIF(Else If) ELSE(Else) ENDIF(Endif) C FLDA IFEQ FLDB C ELSE C ENDIF ITER (Iterate) LEAVE (Leave a DO / FOR Group) C NUM DOWLT 10 C *IN01 IFEQ *ON C EVAL *IN30 = *ON C LEAVE C ELSE C ITER C ENDIF C ENDDO CONDITION BASED OPCODE SELECT (Begin a Select Group) C SELECT C WHEN X=1 * Sequence 1 C WHEN ((Y = 2) AND (X < 10)) * Sequence 2 C OTHER * Sequence 3 C ENDSL SUBROUTINE RELATED OPCODE BEGSR (Begin Sub Routine) ±C SUBRTB BEGSR LEAVESR (Leave a Sub Routine) ±C LEAVESR ENDSR (End Sub-Routine) ±C ENDSR SUBRTB EXSR (Invoke Sub-Routine) ±C EXSR @CMD OPCODE CHECK (Check Character) ±C CHECK String Num COMP (Compare) ± C FLDA COMP FLDB 111213 CAT (Concatenate two Strings) ± C NAME CAT FIRST RESULT DSPLY (Display) ± C DSPLY Num OPCODE CALL (Call a program) ± C CALL PROGA EXFMT (Write/ Then Read Format) ±C EXFMT EMPDTL EXTRCT(Extract Date / Time / Timestamp) ±C Extrct ISODate:*M MonthD EXCEPT (Calculation Time Output) ± C EXCEPT HDG OPCODE PARM (Identify Parameters) ±C FieldA PARM FieldB FieldC PLIST (Identify Parameter List) ±C PLIST1 PLIST RETURN (Return to Caller) ±C RETURN 7 ±C RETURN Parm * 15 DISPLAY FILE Display files are DDS files that enable us to create menus and screens to interact with the user. It can have several records Records may or may not overlap each other SDA application is used for creating the Display Files Subfile is a type of display file. SUBFILES SUBFILES It is used in display file programming to allow the users to handle lists of columnar data in a easier way. It makes the program designing simple. It is a two step process ± Loading Data into a Subfile ± Displaying the Subfile data. It consists of two Record Formats ± Subfile Format ± Subfile Control Format SUBFILES Subfile Format holds the Records that has to be displayed Subfile Control Format defines how many records it can contain and display. It is of three types ± Load All ± Expanding ± Single Page. LOAD ALL SUBFILE SFLSIZE > SFLPAGE All the records are loaded into the Subfile in one shot and displayed. Rolling options are taken care by the system. EXPANDING SUBFILE SFLSIZE > SFLPAGE A Specific number of records are loaded into the subfile format and then displayed. Roll back option has to be programmed by the user. SINGLE PAGE SUBFILE SFLSIZE = SFLPAGE The number of records that can be displayed only is loaded into the subfile and then displayed. Roll back and Roll Forward is to be programmed by the user KEYWORDS SFLCTL Subfile control format SFLDSPCTL Subfile Display Control SFLDSP Subfile Display SFLPAGE This describes how many records that can be displayed in the screen. SFLSIZE - This describes how many records the Subfile can hold. SFLCLR To clear a subfile. SPOOL FILE It helps to manage data targeted for externally attached devices. Holds output data until it can be printed. BUILT-IN FUNCTIONS %ADDRESS IF COND(&P1 *NE %ADDRESS(&C1) %BINARY DCL VAR(&N) TYPE(*DEC) LEN(5 0) VALUE(107) DCL VAR(&B4) TYPE(*CHAR) LEN(4) CHGVAR %BIN(&B4) &N %SUBSTRING DCL &A *CHAR VALUE(ABC) DCL &B *CHAR VALUE(DEF) IF (%SST(&A 1 2) *EQ %SUBSTRING(&B 1 2)) + CALL CUS210 %SWITCH IF (%SWITCH(11XXXXXX)) CALLPRC PROCA IF (%SWITCH(10XXXXXX)) CALLPRC PROCB