3.17.2 Database File Attributes Maintenance
A screen similar to this example is displayed when the option to review or change database file attributes is chosen from the file definition menu. This example is a non-RDMLX view:
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For an RDMLX partition, the view will be slightly different:
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Working from the Database File Attributes screen you can:
- Review the existing database attributes of the physical file and all logical files associated with the file definition. Use the ROLL keys to scroll backwards and forwards through the list of logical files that is shown at the bottom of the screen.
- Change the existing database attributes of the physical file and all logical files associated with the file definition. To do this use the Change function key to make the screen input capable and make the desired changes.
Input Options
These input options apply to reviewing or changing the attributes of database files associated with the LANSA file definition.
The input options are described in two parts:
Input Options - Physical File Attributes (Upper Half Of Screen)
Input Options - Logical File Attributes (Lower Half of Screen)
Input Options - Physical File Attributes (Upper Half Of Screen)
Description
Specifies the description of the physical file. If no description is specified it will default to the physical file name. This description is used within LANSA and within the operating system to aid system users in identifying the file.
OS/400 HSTab
Specifies whether this file definition and associated logical views should be mirrored into a high speed OS/400 User Index to allow more rapid access in "read only" situations.
YES indicates that the file should be mirrored in a high speed index. NO indicates that the file should not be mirrored in a high speed index. NO is the default value.
For further information refer to More About High Speed Tables.
Maintained By
Specifies who is to create and maintain this file definition. Allowable values are:
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LANSA |
Indicates that the actual physical and logical files that result from this file definition are to be maintained (i.e. created, changed and deleted) by the LANSA system. |
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OTHER |
Indicates that the actual physical and logical files associated with this file definition are to be maintained (i.e. created, changed and deleted) by some OTHER system or mechanism. Use this option when you wish to load the definition of an existing file into LANSA, thus making the file accessible through LANSA but do not wish to have LANSA responsible for the setup and maintenance of the associated physical and logical files. If this option is used it is possible to use the facility "Load definition of file not maintained by LANSA" from the file definition menu to automatically load the definition of associated physical and logical files into the LANSA system. Refer to 3.19 Load the Definition of a File NOT Maintained by LANSA for more information about this facility. |
WARNING: If this value is shown as OTHER, use EXTREME CAUTION when changing it to LANSA. You are saying that the future setup and maintenance of this file is to be done by LANSA. This may upset existing applications that already use the file. It is recommended that you do NOT make this type of change unless you are fully aware of ALL the ramifications. Contact your product vendor for further advice.
Record Format Name
Specifies the record format name to be assigned to the physical file record. When the file definition was first set up this value was initialized to be the same as the file name. Change name as desired. The name specified must conform to IBM i record format naming conventions and must be no more than 10 characters long. It is recorded that no more than 8 characters are used.
I/O Mod Lib
Specifies what library the file's I/O module will reside.
F, which is the default value, indicates that the I/O module will reside in the same library as the file.
M, which is the other allowable value, indicates that the I/O module will reside in the partition module library.
Commitment
Specifies whether or not the file is to be placed under commitment control. Refer to the appropriate IBM supplied manuals for more details of commitment control and commitment control processing. Commitment control is a facility provided by the IBM i operating systems.
Allowable values for this field are:
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YES |
The file is to be under commitment control |
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NO |
The file is not to be under commitment control |
When a file definition is first created the default value for commitment control (YES or NO) is set from the system definition data area. Refer to System Definition Data Areas for more details and information about how to change the system default values.
Note: Using this option indicates that the file is to be placed under commitment control all the time, in all applications. To selectively use (or not use) commitment control, refer to the *PGMCOMMIT / *NOPGMCOMMIT options of the FUNCTION command in the .
AUTOCOMMIT Parameter
This option was made redundant by LANSA version 4.0 at program change level E5.
Share
Specifies whether or not this file (and any of its associated logical views) should be opened with the option to share an open data path.
Despite the fact that IBM recommend data path sharing as one of the fundamental design considerations for efficient applications, the default for LANSA created files is NO (do not share open data paths). The reason for this is that the I/O module concept implicitly emulates an open data path, because one active I/O module is shared by all RDML functions (within a job) that are accessing a file.
Generally use option NO (do not share an open data path), except in the special situation where the file is only being used as a "joined record format" for data that is dynamically created by the IBM OPNQRYF (open query file) command.
Note that this value only affects the way that the I/O module (and hence RDML applications) open the file at run time.
To actually get the physical file and logical files defined to the operating system as SHARE(*YES) or SHARE(*NO) for the benefit of external application programs, refer to the CRTPF/CHGPF and CRTLF/CHGLF options below.
Note: This option relates to the opening of the file's open data path when used in I/O modules and *DBOPTIMISE programs, this option does not relate to the creation or changing of the database file attributes.
Secure
Specifies whether or not this file (and any of its associated logical views) should be opened with the option to be secured from file override commands already issued by higher level program(s).
Refer to the appropriate IBM supplied manual(s) for more information about the SECURE parameter on file override commands and the effects of using it.
The default for this field is YES. Do not change this value unless you understand what it does and how it is used.
Strip Debug
Specifies whether or not the RPG I/O module associated with the file definition should have its associated debug symbolic information removed. This information is only required in two situations:
- When attempting to use the IBM supplied debugging aids with the compiled RPG I/O module.
Since these situations are relatively rare, the default for this field is YES (debugging information should be stripped). By using this option, the size of the compiled I/O module will typically be reduced by 40 to 60%. This size reduction has no bearing on execution speed, just on the size of the compiled object.
To enable RPG I/O modules to be debugged, use option NO (debug information should not be stripped).
Suppress IOM0034 Msg
When an I/O module is used to access a file that has never been directly defined to LANSA, it issues message IOM0034 indicating that no LANSA level security information exists for the file.
To suppress this message specify YES.
To allow this message to be issued, specify NO (message is not to be suppressed).
The default value for this option is NO.
Ignore Decimal Error
Specifies whether or not the RPG I/O module associated with the file definition should be compiled with the IGNDECERR (ignore decimal data error) option. The default is NO. The only other possible value is YES. The use of YES is not recommended.
While the IGNDECERR option is available in LANSA, the IBM warnings about using this option still apply. Should using this option cause problems your product vendor may assist you in correcting them, but obviously cannot accept any responsibility for the problem or its cause. Do not use this option unless absolutely necessary. Refer to the IBM i CRTRPGPGM command for more details of the IBM warnings and disclaimer before attempting to use this option.
I/O Module
Specifies whether or not an I/O module is required for this file and its associated logical views.
YES, which is the default value, indicates that an I/O module is required for this file and its associated logical views.
NO, which is the other allowable value, indicates that an I/O module is not required for this file or any of its associated logical views.
To effectively use NO, you must use the FUNCTION RDML command with the OPTIONS(*DBOPTIMISE) keyword in every RDML function that attempts to access this file or any of its associated logical views. If this command is omitted from the RDML function it will compile correctly, but at execution time fail because calls it places to the non-existent I/O module will be unresolved.
It is strongly recommended that you do not use NO until you have had some experience with the LANSA product and are familiar with the concept and workings of I/O modules.
Refer to Using *DBOPTIMIZE / *DBOPTIMIZE_Batch and the FUNCTION command in the for more details of how to set up and use a system without using I/O modules.
Note that if this value is changed from YES to NO, and the resultant change made operational, any existing I/O module will be automatically deleted. After this has been done, all existing RDML functions that access this file without using *DBOPTIMISE will fail when used. This is because they are attempting to resolve to a now non-existent I/O module. In such cases, add the *DBOPTIMISE option to the RDML functions involved and recompile them.
Create Batch Ctl Rcd
Specifies whether or not other database files that perform batch control totaling against this file should be allowed to automatically create missing "batch" records in this file.
NO, which is the default, specifies that when a batch control record cannot be found in this file, the other file operation should fail with error message IOM0032.
YES, which is the other allowable value, indicates that when a batch control record cannot be found in this file, the other file's I/O operation is allowed to automatically create one.
The other file's I/O operation is modified to create the missing batch control record in this file like this:
- All fields in this file's record format are set to blanks (alphanumeric fields) or zero (numeric fields)
- The field(s) or value(s) from the other file that were used as key(s) to access the batch control record in this file are mapped into their corresponding field(s) in this file. This mapping is by key matching, not by name.
- The new record thus assembled is inserted into this file.
Before attempting to use this option ensure that you understand the ramifications of using it and then thoroughly test all resulting applications.
Also note that when changing this option, it is necessary to make the amendment to this file operational. Additionally, all I/O modules for other files that perform batch control totaling against this file must also be (re)compiled.
ALTSEQ
Specifies the name of an Alternate Collating Table to be used when sequencing the records for retrieval on a Keyed file. The Alternate Collating Table name if specified is not validated that it actually exists. When attempting to use any file that has been created with an Alternate Collating Table the library list is used to locate the Table file.
Note: At File Creation time you must have operational rights to the Alternate Collating Table. Alternate Collating sequences are not valid for key fields with a data type of packed decimal. Causes zoned key fields to default to unsigned sequence.
DB triggers
If DB triggers used is YES, then this file will generate operating system level DB triggers.
DB trigger PGM is the name of the program that will be generated to action the DB trigger(s).
CRTPF & CHGPF Parameters
Specifies any additional command parameters that are to be used by LANSA when creating (CRTPF command) or changing (CHGPF command) the physical file.
When the file definition is set up this value is initialized to include SIZE and LVLCHK parameters which are set from the default values specified in the system definition data area. Refer to System Definition Data Areas for more details.
When specifying parameters input them exactly as would be done when entering them through the IBM i command entry facility. Use "keyword" (rather than positional) specification of any parameters required.
Parameters specified are checked for validity. If invalid, the screen will be re-displayed with an error message.
Parameters that can be specified include EXPDATE, MAXMBRS, MAINT, RECOVER, FRCACCPTH, SIZE, ALLOCATE, UNIT, FRCRATIO, WAITFILE, WAITRCD, SHARE, DLTPCT and LVLCHK.
Note: The SHARE parameter relates to the CRTPF & CHGPF command common parameters only, it does not relate to the share an open data option.
Refer to the IBM supplied manual for more details of the CRTPF and CHGPF commands and the associated common parameters.
Input Options - Logical File Attributes (Lower Half of Screen)
Rcd format
Specifies the record format name to be assigned to the logical file record. When the file definition was first set up this value was initialised to be the same as the file name. Change name as desired. Name specified must conform to IBM i record format naming conventions and must be no more than 10 characters long.
Description
Specifies the description of the logical file. If no description is specified it will default to the logical file name. This description is used within LANSA and within the operating system to aid system users in identifying the file.
ALTSEQ
Specifies the name of an Alternate Collating Table to be used when sequencing the records for retrieval on a Keyed file. The Alternate Collating Table name if specified is not validated that it actually exists. When attempting to use any file that has been created with an Alternate Collating Table the library list is used to locate the Table file.
Note: At File Creation time you must have operational rights to the Alternate Collating Table. Alternate Collating sequences are not valid for key fields with a data type of packed decimal. Causes zoned key fields to default to unsigned sequence.
Parameters
Specifies any additional command parameters that are to be used by LANSA when creating (CRTLF command) or changing (CHGLF command) the logical file.
When the file definition is set up this value is initialised to include a LVLCHK parameter which was set from the default specified in the system definition data area. Refer to System Definition Data Areas for more details.
When specifying parameters input them exactly as would be done when entering them through the IBM i command entry facility. Using "keyword" (rather than positional) specification of any parameters required.
Parameters specified are checked for validity. If invalid the screen will be re-displayed with an error message.
Parameters that can be specified include MAXMBRS, RECOVER, FRCACCPTH, UNIT, FMTSLR, FRCRATIO, WAITFILE, WAITRCD, SHARE and LVLCHK.
Note: The SHARE parameter relates to the CRTLF & CHGLF command common parameters only, it does not relate to the share an open data option.
Refer to the IBM supplied manual for more details of the CR073mvxTLF and CHGLF commands and the associated common parameters.