Database creation (BCREATE, BFORMAT, DDL- and SSL- Compiler, BGSIA, BGSSIA, BCALLSI)

The creation of a database requires a number of steps, which are listed in figure 6. The diagram gives you the exact sequence of the preparations you have to make and the programs you have to run.

Figure 6: Stages in the creation of a database

Figure 7: Additional database creation measures

Preparatory stage
1.	The CREATE-FILE command is used to allocate storage space for the realms and files of the compiler database: DBDIR, DBCOM, COSSD and DBSTAT.
Generating the schema
2.	The BCREATE utility routine formats the realms and files of the compiler database:  DBDIR and DBCOM.
3.	The DDL compiler compiles the Schema DDL and stores the compiled result in the DBCOM. It also stores information in the COSSD file which it has set up previously.
4.	SSL compilation is optional, depending on whether the default values for the storage structure are to apply or whether the physical structure of the database is to be defined with SSL. If a storage structure definition (SSL) has already been generated, it has to be compiled at this point. The SSL compiler redefines the record and set entries in DBCOM accordingly.
5.	The BGSIA utility routine sets up the schema information area (SIA) on the basis of the entries in the DBCOM and stores it in the DBDIR. In addition, BGSIA generates the UDSHASH module and stores it in the EAM file.
6.	The UDSHASH module generated by BGSIA has to be entered in the modulelibrary dbname.HASHLIB using the BS2000 utility routine LMS (see the "LMS (BS2000)" manual).
Formatting user realms
7.	The BFORMAT utility routine formats the user realms of the database on the basis of the information stored in the DBDIR. The data is then located in the schema information area (SIA).
Generating the subschema
8.	The DDL compiler compiles the Subschema DDL and stores it in the DBCOM and COSSD.
9.	The BGSSIA utility routine sets up the subschema information area (SSIA) and stores it in the DBDIR.
Defining access rights
10.	The ONLINE-PRIVACY or BPRIVACY utility routine is used to assign access rights (see the chapter "Specifying access authorizations (ONLINE-PRIVACY, BPRIVACY)").

Generating the SSITAB module

The BCALLSI utility routine is required by CALL DML users only. BCALLSI generates the SSITAB module with the subschema information needed by the CALL DML application program.