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Once you have defined your application in the USoft Developer repository, and want to generate the corresponding tables in the Oracle RDBMS, you can have USoft Developer calculate the required table space. Based on this calculation, USoft Developer will implement an Oracle database with enough table space to prevent fragmentation, thereby optimizing performance.
If you have the application tables generated without having the required table space calculated first, USoft Developer will use Oracle defaults.
NOTE 1: Before you can have USoft Developer calculate the required table space, you must at least have defined the site at which the application database will be used. Read "Defining Sites" for more information.
NOTE 2: If you want to make NEW calculations for a particular site, manually delete the information from the Site Indexes and Site Tables tables.
The required table space is calculated as follows:
•For every table (index) defined in the repository, USoft Developer selects the Site table information. If this information is unavailable, it will take defaults. •When the expected number of rows has not been defined in the Site table, the values in the Table table are taken. •When these, too, have not been defined, the system defaults are taken (initial 1000, next 500). •The values for "percentage null" and "percentage full" at the column level are retrieved from the repository. If the "percentage null" has not been defined, USoft Developer takes it to be "0" (zero) if the field is mandatory, and otherwise it is taken to be "50".
If the "percentage full" has not been defined, USoft Developer uses 50.
•With the derived values for the number of rows, the "percentage full", and the "percentage null" USoft Developer calculates the required disk space, the "percentage free" and the "percentage used", using the information supplied by Oracle (see the Oracle DBA guide for more information). |
After the required values have been calculated (or set to default), USoft Developer inserts one row in the Site table for every table (and index) for which no row is found for the given site. All these tables and indexes are related to the default table space created by USoft Developer.
The default table space is initialized with the default storage values, and is named DEFAULT_project. For the default table space, two data files are defined:
•INIT_project_DEFAULT.DAT •NEXT0_project_DEFAULT.DAT The first file contains the "initial sizes" total, the second file contains the "next sizes" total. Both values are multiplied by 1.01 to have some overflow.
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After the values have been (re)calculated every existing row for a table or index is updated with the new values. When, due to changes in sizes, the sum of the objects defined in one table space exceeds the total size of the data files from the table space, a new data file is added to the table space.
The size of the new file is the missing size multiplied by 1.1, and its name is:
NEXT[n]_project_DEFAULT.DAT
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