After the root dbspace exists, users can create a database. The paragraphs that follow describe the major events that occur on disk when the database server adds a new database.
The database server searches the chunk free-list pages in the dbspace, looking for free space in which to create the system catalog tables. For each system catalog table, in turn, the database server allocates eight contiguous pages, the size of the initial extent of each system catalog table. The tables are created individually and do not necessarily reside next to each other in the dbspace. They can be located in different chunks. As adequate space is found for the initial extent of each table, the pages are allocated, and the associated chunk free-list page is updated.
The database server tracks newly created databases in the database tblspace, which resides in the root dbspace. An entry describing the database is added to the database tblspace in the root dbspace. (See Structure of the Database Tblspace.) For each system catalog table, the database server adds a one-page entry to the tblspace tblspace in the dbspace where the database was built. (See Structure of the Tblspace Tblspace.) Figure 19 illustrates the relationship between the database tblspace entry and the location of the systables system catalog table for the database.
For instructions on how to list your databases after you create them, see monitoring databases in the chapter on managing database-logging status in the IBM Informix: Administrator's Guide.
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