TurboIMAGE/XL Database Management System Reference Manual (30391-90012)
Table Of Contents
- 1 Introduction
- 2 Database Structure and Protection
- 3 Defining a Database
- 4 Using the Database
- 5 TurboIMAGE/XL Library Procedures
- Using TurboIMAGE/XL Intrinsics
- DBBEGIN
- DBCLOSE
- DBCONTROL
- DBDELETE
- DBEND
- DBERROR
- DBEXPLAIN
- DBFIND
- DBGET
- DBINFO
- INTRINSIC NUMBER 402
- Syntax
- Parameters
- Discussion
- Mode 101: Item Number
- Mode 102: Item Name
- Mode 103: Items in Database
- Mode 104: Items in Data Set
- Mode 113: BTREEMODE1 and Wildcard Character
- Mode 201: Set Number
- Mode 202: Set Name
- Mode 203: Sets in Database
- Mode 204: Sets with Item
- Mode 205: Set Capacity
- Mode 206: Number of Data Set Chunks
- Mode 207: Size of Data Set Chunks
- Mode 208: Primary and Actual Capacity
- Mode 209: B-Tree Attachment
- Mode 301: Paths
- Mode 302: Key or Search Item
- Mode 401: Logging
- Mode 402: ILR
- Mode 403: Dynamic Roll-Back
- Mode 404: Logging Subsystem Information
- Mode 406: Database Information
- Mode 501: Subsystem Access
- Mode 502: Critical Item Update
- Modes 8nn: Third-Party Indexing
- Mode 901: Language
- DBLOCK
- DBMEMO
- DBOPEN
- DBPUT
- DBUNLOCK
- DBUPDATE
- DBXBEGIN
- DBXEND
- DBXUNDO
- 6 Host Language Access
- Model Program
- ORDERS Database Model Program
- Main Body of Program
- Opening the Database
- Retrieving All the Records on a Chain (with Item Level Locking)
- Retrieving a Data Entry Using a Record Number
- Retrieving Master Data Using a Key Value
- Retrieving Data Serially (with Set Level Locking)
- Adding an Entry
- Updating an Entry
- Deleting an Entry
- Rewinding a Data Set
- Obtaining Database Information
- Obtaining Error Messages and Explanations
- Closing the Database
- C
- COBOL II
- Defining Data Types, Variables, and Intrinsics
- Main Body of Program
- Opening the Database
- Retrieving All the Records on a Chain (with Item Level Locking)
- Retrieving a Data Entry Using a Record Number
- Retrieving Master Data Using a Key Value
- Retrieving Data Serially (with Set Level Locking)
- Adding an Entry
- Updating an Entry
- Deleting an Entry
- Rewinding a Data Set
- Obtaining Database Information
- Obtaining Error Messages and Explanations
- Closing the Database
- FORTRAN 77
- Pascal
- RPG
- 7 Logging and Recovery
- Database Utilities Used in Logging and Recovery
- Recovery Options
- Logical Transactions
- Dynamic Roll-Back Recovery
- Intrinsic Level Recovery
- Logging Preparation
- Step 1--Checking MPE/iX Logging Configuration
- Step 2--Acquiring Logging Capability
- Step 3--Logging to Tape or Disk
- Step 4--Building a Log File for Logging to Disk
- Step 5--Creating the Log Identifier
- Step 6--Setting the Log Identifier
- Step 7--Setting Flags for the Database Backup Copy
- Step 8--Making a Database Backup Copy
- TurboSTORE/iX 7x24 True-Online Backup
- Logging Status
- Logging Maintenance
- Roll-Forward Recovery
- Roll-Back Recovery
- DBRECOV Commands Used with Roll-Forward and Roll-Back Recovery
- Recovery Tables
- Post-Recovery Options
- The Mirror Database
- 8 Using the Database Utilities
- Restructuring the Database with TurboIMAGE/XL Utilities
- Summary of Utility Routines
- Utility Program Operation
- DBLOAD
- DBRECOV
- >CONTROL
- >EXIT
- >FILE
- >RECOVER
- >ROLLBACK
- >RUN
- DBRESTOR
- DBSTORE
- DBUNLOAD
- DBUTIL
- >>ACTIVATE
- >>ADDINDEX
- >>CREATE
- >>DEACTIVATE
- >>DETACH
- >>DISABLE
- >>DROPINDEX
- >>ENABLE
- >>ERASE
- >>EXIT
- >>HELP
- >>MOVE
- >>PURGE
- >>REBUILDINDEX
- >>REDO
- >>RELEASE
- >>SECURE
- >>SET
- >>SHOW
- Syntax
- Parameters
- Example (Show Users)
- Example Discussion
- Example (Show All)
- Example Discussion
- Example (Show Capacity)
- Format of Show Device List
- Example (Show Device)
- Format of Show Indices
- Example (Show Indices)
- Format of Show Locks List
- Example 1 (Show Locks)
- Example 1 Discussion
- Example 2 (Show Locks)
- Example 2 Discussion
- >>VERIFY
- 9 Using a Remote Database
- 10 Internal Structures and Techniques
- 11 B-Tree Indices
- A Error Messages
- B Results of Multiple Access
- C Database Design Considerations
- D Multiple Calls to DBLOCK
- E TurboIMAGE/XL Log Record Formats
- F MPE/iX Log Record Formats
- G Recovery and Logging Quick Reference
- H TurboIMAGE/XL versus TurboIMAGE/V
Chapter 6 281
Host Language Access
COBOL II
NO ADVANCING
ACCEPT OPTION FREE
ELSE
PERFORM 1100-GET-ERROR-AND-EXPLAIN
END-IF
MOVE "Add Entry to Product Set End" TO TEXT1
MOVE 14 TO TEXTLEN
CALL "DBEND" USING DBNAME, TEXT1, DB-MODE, STATUS1, TEXTLEN
IF CONDITION NOT = 0 THEN
PERFORM 1100-GET-ERROR-AND-EXPLAIN
END-IF
CALL "DBUNLOCK" USING DBNAME, PRODUCT-MASTER, DB-MODE, STATUS1
IF CONDITION NOT = 0 THEN
PERFORM 1100-GET-ERROR-AND-EXPLAIN
END-IF.
Updating an Entry
This paragraph implements the UPDATE-A-CUSTOMER routine of the sample program. The
update process takes place in two phases.
In the first phase, the requested entry is located and retrieved. This is achieved by a call to
DBGET in mode 7. Then, the user provides the new values.
In the second phase, the recently modified values replace the existing entry. This is
implemented using a call to DBUPDATE. Before this call, the paragraph starts a
TurboIMAGE/XL transaction bracketed by calls for locking the volatile item. To retrieve
the entry, DBGET is called in mode 1. This call retrieves the entry located in the previous
stage.
The paragraph must confirm that values retrieved in the first stage are still residing in the
same entry. This should be done before the actual update. If the contents of the buffers are
the same, the paragraph can continue with the operation. Otherwise, it should end the
transaction and release the locks.
The exceptional condition for this paragraph is status 17. This indicates that the requested
entry does not exist or is empty.
******************************************************************
* ACCESS : Mode 1 - Shared Modify Access
*
* Called By: 30-DO-ACTION
*
* Calls : DBGET in mode 7 (calculated)
* DBLOCK in mode 5 (unconditional)
* DBBEGIN in mode 1 (transaction begin)
* DBGET in mode 1 (re-read)
* DBUPDATE in mode 1 (update)
* DBEND in mode 1 (transaction end)
* DBUNLOCK in mode 1 (unlock)
* 1100-GET-ERROR-AND-EXPLAIN
700-UPDATE-A-CUSTOMER.
SET NOT-FOUND TO TRUE
DISPLAY CLEAR SCREEN
DISPLAY "Enter the Account # for The Customer Master"
NO ADVANCING
DISPLAY "---------> " NO ADVANCING