Modify Internals

Cesare Petrizio

Information Builders

Copyright 2007, Information Builders. Slide 1

Copyright 2007, Information Builders. Slide 2

Agenda

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MODIFY Internals

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Database Creation

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Analysis Phase Transaction Processor Transaction Processor Activation Database Processor Database Actions Database Physical Structure Limits Database Logical Structure File Directory Table File Control Block Pointers MODIFY Overview

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FOCUS Database A FOCUS Database is established by:

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CREATE FILE filename

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Initial MODIFY FILE filename

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REBUILD/REBUILD or REBUILD/REORG

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HOLD FORMAT FOCUS

FOCUS Database

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CREATE FILE is required for a FOCUS (or FUSION) database if: MVS/TSO

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Database to be used in SU process

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Database to be used as part of MAINTAIN or COMBINE

MODIFY Internals

Analysis Screen Transactions File Transactions Transaction Processor BINs Log Files Database Database Processor

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Analysis

 Open and CHECK Master File Descriptions  Verify DBA access to file(s)  Determine I/O access modules required  Check DBA and set up access restrictions at SEGMENT and FIELD levels.

 Read and parse the FOCEXEC  Establish VALIDATE statements for VALUE restrictions  Set up memory for Scratch Pad Area if required  Establish DATREC and LINREC  Establish Case Processing tables  If COMPILE, create FOCCOMP and exit.

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MODIFY Internals Analysis

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Work Areas

DATREC – DATabase-RECord   Retrieval of Database Values Maximum size – 32K LINREC – LINe RECord    Retrieval of Transaction Values Maximum size – 32K COMPUTE and VALIDATE fields are extensions to the transaction Copyright 2007, Information Builders. Slide 8

MODIFY Internals Analysis Work Areas

  RECDIS - RECord Description   Field Activation Table Maximum 3072 fields CRTBUF – CRTform BUFfer   Last display of CRTFORM Divided into Screens Copyright 2007, Information Builders. Slide 9

MODIFY Internals Analysis - Work Areas

 SEGACT – SEGment ACTivation    Segment Activation Table Established per CASE Bits to control     Activation Move to DATREC MATCH/NOMATCH SEGTYPE and MATCH logic Copyright 2007, Information Builders. Slide 10

MODIFY Internals Analysis – Special Conditions

 SEGACT- SEGment ACTivation  COMBINE – SYSTEM99 root segment of each database is constructed in FOCSORT  Indexed MODIFY –   Index is treated as root segment If the index is not the key of its segment, key(s) must also be MATCHed   No access to segments higher in the hierarchy UPDATE or REJECT only at entry level (no INCLUDE OR DELETE)  Full access to MODIFY subcommands at lower level segments Copyright 2007, Information Builders. Slide 11

MODIFY Internals Analysis - Work Areas

 SPA (Scratch Pad Area)   Width: (Storage Length of fields * 2) + 1 # Rows: Max of REPEAT n Default 5 rows  Rounded up to nearest 1K Fields:    Every field mentioned in any HOLD REPEAT Every field mentioned in any GETHOLD REPEAT Every field mentioned in CRTFORM field(index) Copyright 2007, Information Builders. Slide 12

MODIFY Internals Order of Processing

  No Cases  Transaction Subroutine   Non-Position Related Commands MATCH/NEXT to ALL segments TOP CASE only  Transaction Subroutine   Non-Position Related Commands MATCH/NEXT to segments specified   Other Cases  Non-position Related Commands in order coded  MATCH/NEXT to segments specified If MATCH/NEXT is coded, all GOTO commands are considered ON MATCH/NOMATCH GOTO … Copyright 2007, Information Builders. Slide 13

MODIFY Internals Order of Processing - MODIFY Premise COMPUTE field/format = ; COMPUTE/VALIDATE field/format = expression Same name and format as other field TOP CASE GOTO/IF ... GOTO/PERFORM MATCH/NEXT prior in case Non-Positional TYPE/COMPUTE/REPEAT...

1 Y 2 Y Y N 3 Y Y Y 4 5 6 Y Y N Y N Y Y N N 7 8 Y Y Y N 9 Y Action Analysis Phase, extend LINREC After first transaction subcommand ON MATCH/NOMATCH ...

Prior to MATCH/NEXT commands Order coded Y Y Y Y Y Y Y Y Y Y

MODIFY Internals Default MATCH/NOMATCH Actions    MATCH * (MATCH all active fields) MATCH * KEYS (MATCH all active keys) MATCH requires a MATCH to all keys:  WARNING – MATCH ASSUMED   Default ON NOMATCH - INCLUDE Default ON MATCH - REJECT Copyright 2007, Information Builders. Slide 15

MODIFY Internals

Analysis Screen Transactions File Transactions Transaction Processor BINs Log Files Database Database Processor

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MODIFY Internals Transaction Processing

 FREEFORM      Default Transaction Type Comma-delimited Maximum LRECL 256 Value Carry-over Comma Dollar (,$) to end transaction

MODIFY FILE CAR DATA ON CCARS END ENGLAND,JAGUAR,V12XKE AUTO,SEDAN,$ CAR=JENSEN,$

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MODIFY Internals Transaction Processing

 PROMPT      Creates comma-delimited file PROMPT field field field SEG.field

END in response to prompt terminates transaction processing PROMPT COUNTRY 5(CAR MODEL) Converts to FREEFORM MODIFY FILE CAR PROMPT COUNTRY CAR MODEL MATCH COUNTRY ON NOMATCH INCLUDE DATA END Copyright 2007, Information Builders. Slide 18

MODIFY Internals Transaction Processing

 FIXFORM  FIXFORM field/format field/format field/Cn Xn  Xn is ignored at the end of any FIXFORM except in TOP CASE   Default format type is A (alpha) Upon reading the transaction, values are moved to LINREC and with necessary conversion.

   Invalid format gives FORMAT rejection FORMAT rejection if not in ACCEPT list.

Read is performed:    TOP CASE FIXFORM ON When required to fulfill request Copyright 2007, Information Builders. Slide 19

MODIFY Internals Transaction Processing

 FIXFORM FROM mastername  Mastername must describe a single segment SUFFIX = FIX FILE     Actual is used to indicate the input format All fields are

conditional

FIELDNAME matches to FIELDNAME or ALIAS Used in HOLD FORMAT FOCUS FOC$HOLD.FEX

MODIFY FILE newfile FIXFORM FROM FOC$HOLD DATA ON FOC$HOLD END Copyright 2007, Information Builders. Slide 20

MODIFY Internals Transaction Processing

 CRTFORM {LINE n} {UPPER/LOWER} {TYPE n} {WIDTH n}    Default Width – 78 columns Default Height -- 24 – TYPE lines Non-conditional field  Blank is acceptable value and will update database 

 Creates FIXFORM transaction Copyright 2007, Information Builders. Slide 21

MODIFY Internals CRTFORM – Source of D., T. fields Henry’s Famous Table Database Field Re-COMPUTE MATCH DATREC NOMATCH Defaults Active?

LINREC Not Active DATREC COMPUTE Field LINREC

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MODIFY Internals Source of Fields Values on CRTFORM 1 Y 2 3 4 Premise INVALID CRTFORM NOCLEAR Index > HOLDCOUNT D.Field or T.field

Database field Compute Field ACTIVE MATCH Y Y Y 5 6 7 8 Y Y N Y Y N Y N Y Y Y Y Y Y N 9 Y Y Y N Source DATREC LINREC CRTBUF Defaults Blanks Y Y Y Y Y Y Y Y Y

MODIFY Internals

Analysis Screen Transactions

Activation

File Transactions Transaction Processor BINs Log Files Database Processor Database

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MODIFY Internals Activation

 FIELD Activation   Controls UPDATE Field is ACTIVE When :    Present on a Transaction Left side of a COMPUTE ACTIVATE issued  Field is Deactivated When:     UPDATE is performed INCLUDE / DELETE at that level Navigation to TOP Case DEACTIVATE issued Copyright 2007, Information Builders. Slide 25

MODIFY Internals Activation

 SEGMENT Activation  Controls   MATCH INCLUDE    Any field on SEGMENT is Activated Segments lower in the hierarchy activated Segment is Deactivated When:     INCLUDE / DELETE at that level Navigation to TOP Case Movement to different segment instance,same level.

DEACTIVATE issue Copyright 2007, Information Builders. Slide 26

MODIFY Internals FIELD and SEGMENT Activation 1 2 FIXFORM field/format or CRTFORM FIXFORM field/Cformat or CRTFORM or CRTFORM

Transaction value = database value COMPUTE field= expression; ACTIVATE field Field already ACTIVE Y 3 Y N Y Y 4 5 Y 6 7 N Y N Y N Y Y Y 8 Y 9 10 Y Y Y N Field Activated SEGMENT Activated Value Moved to LINREC Default Moved to LINREC DATREC Value moved to LINREC Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y

MODIFY Internals FIELD and SEGMENT Deactivation INCLUDE UPDATE DELETE MOVE TO DIFFERENT SEGMENT INSTANCE DEACTIVATE DEACTIVATE RETAIN TOP CASE All fields on SEGMENT Deactivated Field Deactivated SEGMENT Deactivated Default Values to LINREC 1 Y 2 3 4 Y Y Y Y 5 6 Y 7 Y 8 Y Y Y Y Y Y Y Y Y Y Y Y Y Y

MODIFY Internals

Analysis Screen Transactions File Transactions Transaction Processor Log Files BINs Database Processor Database

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MODIFY Internals MATCH

 MATCH keyfield(s)  Using INDEX   SEGTYPE = S1 or SH1 Root Segment  CRTFORM or Trans value < last trans  Beginning of Chain   SEGTYPE = ‘ ‘ SEGTYPE = S[H]n,  Trans Value < last trans  Current Position   SEGTYPE = S0 SEGTYPE = S[H]n  Trans Value > last trans Copyright 2007, Information Builders. Slide 30

MODIFY Internals NOMATCH

 SEGTYPE = S[H]n  Prior to searched value  SEGTYPE = S0  End-of-Chain  SEGTYPE = blank  End-of-Chain  Explicit MODIFY through index MODIFY FILE fn.index

 NO position at NOMATCH Copyright 2007, Information Builders. Slide 31

MODIFY Internals MATCH SEGTYPE = S[H]1 SEGTYPE = S0 SEGTYPE = blank SEGTYPE = S[H]n Top Segment Root key indexed CRTFORM Current Transaction : last Trans Start Beginning of Chain Start Current Position Use Index NOMATCH at END-OF-CHAIN NOMATCH Prior to searched value 1 Y Y Y Y 2 Y 3 Y 4 5 6 7 8 Y Y Y Y Y Y Y N < Y Y N > < > = Y Y Y Y Y Y Y Y Y Y Y Y Y Y

MODIFY Internals Movement to DATREC - local mode

 MATCH keys  ON MATCH CONTINUE  No action (“passing through”)  ON MATCH COMPUTE/CRTFORM/VALIDATE   Move segment instance to DATREC Take required action  MATCH WITH-UNIQUES key    Retrieves host instance + ALL unique child instances ON MATCH COMPUTE/CRTFORM/VALIDATE Unique segments are considered “logical extensions of the parent” Copyright 2007, Information Builders. Slide 33

MODIFY Internals Movement to DATREC

   NEXT field  Entire instance moved to DATREC  Key fields are copied to LINREC COMPUTE/VALIDATE RETURN/I1 = FIND (val IN filename)  Index page read into BINs (if necessary)  Only RETURN is populated (1 or 0) COMPUTE/VALIDATE RETURN = LOOKUP([SEG.crfield] condition);  Crfield - JOIN segment or [DKU/KU]    JOIN and COMBINE are mutually exclusive Value for field(s) moved to DATREC and LINREC Crfield value taken from LINREC Copyright 2007, Information Builders. Slide 34

MODIFY Internals MATCH MATCH SU ON MATCH COMPUTE NEXT FIND LOOKUP MOVE FROM DATABASE TO BINS MOVE FROM BINS TO DATREC MOVE INDEX PAGE TO BINS SEND DATREC TO USER MOVE KEYS FROM DATREC TO LINREC MOVE NON-KEYS FROM DATREC TO LINREC 1 Y Y 2 Y N 3 Y N Y 4 Y 5 Y 6 7 N Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y

MODIFY Internals

Analysis Screen Transactions File Transactions Transaction Processor BINs

Database actions

Log Files Database Processor Database

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MODIFY Internals Database Actions

 INCLUDE    Values moved from LINREC To BINS All Active Child Segments INCLUDED Non-SU deleted space may be re-used  UPDATE  Specified ACTIVE fields are updated from LINREC to BINS  MATCH WITH-UNIQUES UPDATE might be INCLUDE of UNIQUE segment  DELETE  Segment and all descendant segments are deleted Copyright 2007, Information Builders. Slide 37

MODIFY Internals INDEX Actions

 INCLUDE   New value and address are moved to index page Full index pages require index page split  UPDATE    Index searched and old value deleted New value and address moved to index page Full index pages require index page split  DELETE  Index searched and old value deleted Copyright 2007, Information Builders. Slide 38

MODIFY Internals Transaction Counter

    Transaction Counter is incremented in first PHYSICAL case with data collection.

CHECK nnnn  After nnnn transactions, COMMIT is issued Default CHECK (no COMMIT specified in MODIFY)   LOCAL  CHECK 10 CRTFORM  SU   CHECK 1,000 FIXFORM CHECK 1 CRTFORM CHECK 1,000 FIXFORM SU – CHECK saves all users changes Copyright 2007, Information Builders. Slide 39

MODIFY Internals Transaction Counter

    Changes are made into BINs SU and COMMIT  Local User changes to Local Bins SU, not COMMIT  Local User changes sent to Sink and sink BINs “Forced CHECK”  Move from BINs to Database  If SHADOW is ON for that database, move to shadow pages.

 CHECK or COMMIT   Move any additional pages from BINS to database If SHADOW = ON, update SHADOW directory Copyright 2007, Information Builders. Slide 40

QUESTIONS Thanks for Coming

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