Traditional system interface considerations

An SQL table is a database physical file with one member (partition). Therefore, when the file is accessed by a traditional system application, the traditional system application reads and writes to the member by opening the file's member.

When the file (SQL table) becomes partitioned, the file becomes a multimember file and the traditional system application needs to specify the member name (partition name). The traditional system application can avoid having to specify a member name when reading or writing data by changing the application to use an SQL index that is based on all the members of the physical file.

For example, if the user created an SQL index with the following code,

CREATE INDEX LIBNAME.INDEXNAME 
   ON LIBNAME.TABLENAME(COLUMNNAME)
   NOT PARTITIONED

The traditional system application can read and write data from the partitioned table without having to know how the data is partitioned.

When the table becomes partitioned (becomes a multimember file), any traditional system operation that was previously done to the table must be done for each member of the multimember file. For example, RGZPFM FILE(LIBNAME/TABLENAME) only reorganizes the *FIRST member. For a partitioned table, you need to use the Reorganize Physical File Member (RGZPFM) command for each member. The Display File Description (DSPFD) command, DSPFD FILE(LIBNAME/TABLENAME) TYPE(*MBRLIST), lists all members of the file.