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Appendix C File Qualifications This appendix discusses the file qualifications for the Windows, UNIX, and VMS operating systems. It begins with a general discussion of file categories, file descriptors, and file names. Specific discussions for each operating system provide details for file descriptors, file protection, and file-naming conventions. Each section contains systemspecific examples. Categories of Database Files A database resides on a number of files. All of these files must be defined in the Structural Data Model (SDM). The 4 categories of database files are described below: Data Files The actual data records and indexes can be stored in several host system data files. One of these files is used to hold queued records. Journal Files The journal files are used to record each change made to the database and are used to recover data files and the DDB from media failure. File Qualifications 695 Definition Database (DDB) The definition database holds a description of the entire database and also indicates where all of the other files are located. File Definitions on Host Systems Every file has a unique set of attributes which are used to identify, locate, and protect the file. These attributes are specified in a special format called the file descriptor. One of the attributes, the file name, uniquely identifies the file. File Descriptors The format of the file descriptor (FD) depends on the host system because each system uses a slightly different set of attributes. Each of the host system file descriptor formats is discussed in detail in the BASIS Reference manual. File Names On every system, the file descriptor for a permanent file contains a filename. The filename is always required. 696 File Qualifications Windows This section describes database files for Windows operating systems. File Descriptor For a detailed description of Windows file descriptors, see BASIS Reference, “Windows System Specifics.” File Protection The owner of the database is the user who created the DDB file and its journals. This user, known as the DBA, should also INITIALIZE the record database. The DBA is then the owner of all of the database files and has the authority to determine all permissions (security settings) for other users. You can view and modify file security by accessing the File Manager and selecting the file. Once selected, go to the Security menu and select the Permissions option. If you have permission to view the Security for that file, a dialog box where you can add users and groups to or remove users and groups from the access list will be displayed. You can also alter permissions granted to groups, and you can adjust permissions granted to certain individuals even if they belong to groups that have different levels of permissions. For example, in the Windows File manager under the Security menu, you might see that: Persons designated as: Have these permissions: File owner (DBA) Read, write, and execute (RWX) DM_PROD Read, write, and execute (RWX) System Read, write, and execute (RWX) If permissions are set up in the manner shown above, only the DBA and members of the group can write to or modify the file. File Qualifications 697 Granting Permissions to the BASIS Kernel To ensure that the BASIS Kernel can access the files, the Kernel should run under the username DMPROD. DMPROD (the Kernel) must be part of the DM_PROD group in order to access the databases. This will allow the Kernel access to the database files unless and until its file permissions are intentionally changed. For more information about the use of the Windows Security menu, see your Windows documentation. The database files may reside in any directory and be owned by any user. All of the file descriptors used for the files should be fully qualified. Database File-Naming Conventions The file descriptors for your database files should include a meaningful file name identifying the database. The file name should identify the function of the file. The file names should also include file numbers and/or version numbers if they are used. The following file-naming conventions are recommended for use in all database file definitions. Note: Generated file descriptors which appear here are in lowercase. However, the file descriptor can be entered in either upper- or lowercase. Definition Database files: Definition Database File: dbname.ddb DDB Journal File A: dbname.dja DDB Journal File B: dbname.djb DDB Journal A Backup Job: dbname.dbja DDB Journal B Backup Job: dbname.dbjb 698 File Qualifications Record Database files (single file database): Record Database File: dbname.rdb RDB Journal File A: dbname.rja RDB Journal File B: dbname.rjb RDB Journal A Backup Job: dbname.rbja RDB Journal B Backup Job: dbname.rbjb RDB Journal File A Copy: dbname.rjac RDB Journal File B Copy: dbname.rjbc Record Database files (multifile/multiversion database): Record Database Files: dbname.rdb_fnn_vnn RDB Journal File A: dbname.rja_vnn RDB Journal File B: dbname.rjb_vnn RDB Journal A Backup Job: dbname.rja_bj_vnn RDB Journal B Backup Job: dbname.rjb_bj_vnn RDB Journal File A Copy: dbname.rjac_vnn RDB Journal File B Copy: dbname.rjbc_vnn Listed below are some notes regarding the file-naming conventions for Windows: “fnn” is the file number (1:63) and “vnn” is the version number (0:99). The “_vnn” is not needed unless versions are being used with the database. The file descriptor can be entered in either upper- or lowercase. File Qualifications 699 Examples 1. 2. For the first example, suppose the TOUR database has one DDB file and one RDB file. There is only one version of the TOUR database. The following file descriptors are used: DDB File: tour.ddb DDB Journal File A: tour.dja DDB Journal File B: tour.djb RDB Files: tour.rdb RDB Journal File A: tour.rja RDB Journal File B: tour.rjb In the next example, suppose the TOUR database has one DDB file and three RDB files. There are two versions of the TOUR database. The following file descriptors are used: DDB File: tour.ddb DDB Journal File A: tour.dja DDB Journal File B: tour.djb DDB Journal A Backup Job File: tour.dja_bj DDB Journal B Backup Job File: tour.djb_bj RDB File 1, Version 0: tour.rdb_f01_v00 RDB File 2, Version 0: tour.rdb_f02_v00 700 File Qualifications 3. RDB File 3, Version 0: tour.rdb_f03_v00 RDB Journal File A, Version 0: tour.rja_v00 RDB Journal File B, Version 0: tour.rjb_v00 RDB Journal A Backup Job File, Version 0: tour.rja_bj_v00 RDB Journal B Backup Job File, Version 0: tour.rjb_bj_v00 RDB File 1, Version 1: tour.rdb_f01_v01 RDB File 2, Version 1: tour.rdb_f02_v01 RDB File 3, Version 1: tour.rdb_f03_v01 RDB Journal File A, Version 1: tour.rja_v01 RDB Journal File B, Version 1: tour.rjb_v01 RDB Journal A Backup Job File, Version 1: tour.rja_bj_v01 RDB Journal B Backup Job File, Version 1: tour.rjb_bj_v01 The following are fully qualified pathnames. 'C:\company\master' '\\myserver\myshare\payroll\master' 4. The following is a partially qualified path with the current path prefixed to the beginning. 'payroll\master' 5. This is a filename with the current path prefixed to the beginning. 'master' File Qualifications 701 6. This is a logical name where MASTER is an environment variable. '%MASTER%' 7. 8. When the file is to be referenced (e.g., in DMSA), wildcards (*) can be specified to match any number of characters in the file name or path. '*.prc' files ending in .prc 'dept*.prc' .prc files starting with dept 'tour*' all files starting with tour To match a single character in a file name or path, the question mark can be used. 'tour.dj?' matches both DDB journal files (dja and djb) UNIX This section describes database files for the UNIX operating system. File Descriptor For a detailed description of UNIX file descriptors, see BASIS Reference, “UNIX System Specifics.” File Protection The owner of the database is the DBA who created the DDB file and its journals. This DBA should also INITIALIZE the record database. This DBA is then the owner of all of the database files (since the DBA’s UID matches the UID of the files). The DMDBA module sets the file protection as: chmod ug+rwx, o-rwx file_name which can be changed by the owner of the file. With these protections, only the file’s owner and members of the file’s group can gain access to the file. To insure that the BASIS Kernel can access the files, the database group will be the group that the BASIS 702 File Qualifications Kernel executes under (the Kernel’s GID will match the GID of the files). The DBA who is the owner of the file need not belong to this group. The database files may reside in any directory and be owned by any user. All of the file descriptors used for the files should be fully qualified. File-Naming Conventions The file descriptors for your database files should include a meaningful file name identifying the database. The file name should identify the function of the file. The file names should also include file numbers and/or version numbers if they are used. The following file-naming conventions are recommended for use in all database file definitions. Note: The uppercase letters show the predefined portions of the file descriptor. Generated file descriptors are in lowercase. Definition Database files: Definition Database File: DM_dbname/DDB DDB Journal File A: DM_dbname/DJA DDB Journal File B: DM_dbname/DJB DDB Journal A Backup Job: DM_dbname/DJA_BJ DDB Journal B Backup Job: DM_dbname/DJB_BJ File Qualifications 703 Record Database files (single file database): Record Database File: DM_dbname/RDB RDB Journal File A: DM_dbname/RJA RDB Journal File B: DM_dbname/RJB RDB Journal A Backup Job: DM_dbname/RJA_BJ RDB Journal B Backup Job: DM_dbname/RJB_BJ RDB Journal File A Copy: DM_dbname/RJAC RDB Journal File B Copy: DM_dbname/RJBC 704 File Qualifications Record Database files (multi-file/multi-version database): Record Database Files: DM_dbname/RDB_Fnn_Vvv RDB Journal File A: DM_dbname/RJA_Vvv RDB Journal File B: DM_dbname/RJB_Vvv RDB Journal A Backup Job: DM_dbname/RJA_BJ_Vvv RDB Journal B Backup Job: DM_dbname/RJB_BJ_Vvv RDB Journal File A Copy: DM_dbname/RJAC_Vvv RDB Journal File B Copy: DM_dbname/RJBC_Vvv Listed below are some notes regarding the file-naming conventions for UNIX: “nn” is the file number (1:63) and “vv” is the version number (0:99) The “_Vvv” is not needed unless versions are being used with the database. This recommendation requires the directory “DM_dbname” to exist and places all files in that directory. For this reason, you should specify a high level directory for the DATABASE and JOURNAL_DIRECTORY parameters of the GENERATE_SDM. The entire file descriptor should always be entered in lowercase. File Qualifications 705 Examples 1. 2. For the first example, suppose the TOUR database has one DDB file and one RDB file. There is only one version of the TOUR database. The following file descriptors are used: DDB File: dm_tour/ddb DDB Journal File A: dm_tour/dja DDB Journal File B: dm_tour/djb RDB Files: dm_tour/rdb RDB Journal File A: dm_tour/rja RDB Journal File B: dm_tour/rjb In the next example, suppose the TOUR database has one DDB file and three RDB files. There are two versions of the TOUR database. The following file descriptors are used: DDB File: dm_tour/ddb DDB Journal File A: dm_tour/dja DDB Journal File B: dm_tour/djb DDB Journal A Backup Job File: dm_tour/dja_bj DDB Journal B Backup Job File: dm_tour/djb_bj RDB File 1, Version 0: dm_tour/rdb_f01 RDB File 2, Version 0: dm_tour/rdb_f02 RDB File 3, Version 0: dm_tour/rdb_f03 706 File Qualifications 3. RDB Journal File A, Version 0: dm_tour/rja RDB Journal File B, Version 0: dm_tour/rjb RDB Journal A Backup Job File, Version 0: dm_tour/rja_bj RDB Journal B Backup Job File, Version 0: dm_tour/rjb_bj RDB File 1, Version 1: dm_tour/rdb_f01_v01 RDB File 2, Version 1: dm_tour/rdb_f02_v01 RDB File 3, Version 1: dm_tour/rdb_f03_v01 RDB Journal File A, Version 1: dm_tour/rja_v01 RDB Journal File B, Version 1: dm_tour/rjb_v01 RDB Journal A Backup Job File, Version 1: dm_tour/rja_bj_v01 RDB Journal B Backup Job File, Version 1: dm_tour/rjb_bj_v01 The following are fully qualified pathnames. '/company/master' '/company/payroll/master' 4. The following is a partially qualified path with the current path prefixed to the beginning. 'payroll/master' 5. This is a filename with the current path prefixed to the beginning. 'master' 6. This is a logical name where MASTER is an environment variable. '$MASTER' File Qualifications 707 7. 8. When the file is to be referenced (e.g., in DMSA), wildcards (*) can be specified to match any number of characters in the file name or path. '*.prc' files ending in .prc 'dept*.prc' .prc files starting with dept 'tour*' all files starting with tour To match a single character in a file name or path, the question mark can be used. 'dm_tour/dj?' matches both DDB journal files (dja and djb) VMS This section describes database files for the VMS operating system. File Descriptor For a detailed description of VMS file descriptors, see BASIS Reference, “VMS System Specifics.” File Protection The owner of a database is the database administrator (DBA) who creates the database definition (DDB) file and its journal files. The same DBA should also INITIALIZE the Record Database. This DBA is then the owner of all the database files since the DBA’s user identification code (UIC) matches the owner UIC of the files. The database files may reside in any directory and be owned by any member of any group. All file descriptors used for the files should be fully qualified. If any logical names are used, these names must be known to the Kernel. (See “Logical File Names.”) File protection can be changed by the file owner. The DMDBA module sets file protection as: SET PROTECTION=(SYSTEM:RWE,GROUP:RWE,OWNER:RWE, WORLD) With these protections, only the file owner, members of the owner’s group, and the VMS system software can gain access to the file. The Kernel is granted SYSPRV privilege so that, as a piece of system software, it can access the files. 708 File Qualifications Database File-Naming Conventions The file descriptors for your database files should include a meaningful file name identifying the database. The file type should identify the function of the file. The file types should also include file numbers and/or version numbers if they are used. The following file-naming conventions are recommended for use in all database definitions. Definition Database Files: Definition Database File: DM_dbname.DDB DDB Journal File A: DM_dbname.DJA DDB Journal File B: DM_dbname.DJB DDB Journal A Backup Job: DM_dbname.DJA_BJ RDB Journal B Backup Job: DM_dbname.DJB_BJ Record Database Files (single file database): Record Database File: DM_dbname.RDB RDB Journal File A: DM_dbname.RJA RDB Journal File B: DM_dbname.RJB RDB Journal A Backup Job File: DM_dbname.RJA_BJ RDB Journal B Backup Job File: DM_dbname.RJB_BJ RDB Journal File A Copy: DM_dbname.RJAC DDB Journal File B Copy: DM_dbname.RJBC File Qualifications 709 Record Database Files (multi-file/multi-version database): Record Database Files: DM_dbname.RDB_Fnn_Vnn RDB Journal File A: DM_dbname.RJA_Vnn RDB Journal File B: DM_dbname.RJB_Vnn RDB Journal A Backup Job File: DM_dbname.RJA_BJ_Vnn RDB Journal B Backup Job File: DM_dbname.RJB_BJ_Vnn RDB Journal File A Copy: DM_dbname.RJAC_Vnn RDB Journal File B Copy: DM_dbname.RJBC_Vnn Fnn (File number) When multiple files are used, nn indicates the number of the file (01:63). If the Record Database (RDB) is contained within a single file, the Fnn portion of the filename is not used. Vnn (Version number) Indicates the version number (01:99) when multiple versions of the file exist. The Vnn portion of the filename is not used for version 0 of RDB files. 710 File Qualifications Examples 1. 2. For the first example, suppose the TOUR database has one DDB file and one RDB file. There is only one version of the TOUR database. The following file descriptors are used: DDB File: DM_TOUR.DDB DDB Journal File A: DM_TOUR.DJA DDB Journal File B: DM_TOUR.DJB RDB Files: DM_TOUR.RDB RDB Journal File A: DM_TOUR.RJA RDB Journal File B: DM_TOUR.RJB In this example, suppose the TOUR database has one DDB file and three RDB files. There are two versions of the TOUR database. The following file descriptors are used: DDB File: DM_TOUR.DDB DDB Journal File A: DM_TOUR.DJA DDB Journal File B: DM_TOUR.DJB DDB Journal A Backup Job File: DM_TOUR.DJA_BJ DDB Journal B Backup Job File: DM_TOUR.DJB_BJ RDB File 1, Version 0: DM_TOUR.RDB_F01 RDB File 2, Version 0: DM_TOUR.RDB_F02 RDB File 3, Version 0: DM_TOUR.RDB_F03 RDB Journal File A, Version 0: DM_TOUR.RJA File Qualifications 711 RDB Journal File B, Version 0: DM_TOUR.RJB RDB Journal A Backup Job File, Version 0: DM_TOUR.RJA_BJ RDB Journal B Backup Job File, Version 0: DM_TOUR.RJB_BJ RDB File 1, Version 1: DM_TOUR.RDB_F01_V01 RDB File 2, Version 1: DM_TOUR.RDB_F02_V01 RDB File 3, Version 1: DM_TOUR.RDB_F03_V01 RDB Journal File A, Version 1: DM_TOUR.RJA_V01 RDB Journal File B, Version 1: DM_TOUR.RJB_V01 RDB Journal A Backup Job File, Version 1: DM_TOUR.RJA_BJ_V01 RDB Journal B Backup Job File, Version 1: DM_TOUR.RJB_BJ_V01 712 File Qualifications