Solution Guide for Migrating Oracle on UNIX to SQL Server - Willy .Net

<strong>Solution</strong> <strong>Guide</strong> <strong>for</strong> <strong>Migrating</strong> <strong>Oracle</strong> on UNIX to SQL Server on Windows 87Start by compiling a list of tablespaces that contain objects belonging to the schema andgather the following related in<strong>for</strong>mation:● Tablespace name.● Status. The status of an <strong>Oracle</strong> tablespace may be either ONLINE, OFFLINE, orREAD ONLY. If a tablespace is OFFLINE, then a decision has to be made if it isrequired to be migrated. Data in an offline tablespace cannot be accessed and ithas to be brought online <strong>for</strong> migration.● Tablespace contents. Only tablespaces whose tablespace content attribute is setto PERMANENT have to be migrated.● Logging attribute. Tablespaces may be set to LOGGING or NOLOGGING, whichspecifies the default characteristic <strong>for</strong> bulk operations against the objects in thetablespace.Note In SQL Server, the attributes of status, tablespace contents, and logging are setat the database level and not the filegroup level. If an <strong>Oracle</strong> schema has tablespaceswith more than one value <strong>for</strong> these attributes, more than one database will have to becreated in SQL Server. For example, if a schema uses two tablespaces (one isONLINE and the other READ ONLY), then the two tablespaces have to be mapped totwo separate databases in SQL Server. The two databases can then be set to ONLINEand READ_ONLY, respectively, using the state options available in SQL Server.Gather the following in<strong>for</strong>mation <strong>for</strong> each of the datafiles in the tablespaces:● File name● File size● File autoextensibility● Maximum file size● File auto extension incrementFrom the in<strong>for</strong>mation gathered about tablespaces and their datafiles, produce a map <strong>for</strong>the databases, filegroups. and datafiles to be created in SQL Server as shown in Figure6.2.Create Databases <strong>for</strong> the SchemaTo migrate the schemas from <strong>Oracle</strong>, databases are created in SQL Server <strong>for</strong> theschemas. The databases will hold the schema objects and their data. This sectionprovides details on how to create databases in SQL Server.To an <strong>Oracle</strong> DBA, creating a database means creating an entire database system thatcontains control files, redo logs, data dictionary and temporary tablespace. InSQL Server, these tasks are accomplished as part of the installation process. Hencecreating a database in SQL Server implies adding a user database to the already existingsystem databases. Members of the fixed server roles sysadmin and dbcreator, or anyuser with such privileges, can create a database. By default, the creator of the databasebecomes the owner of the database.Databases can be created either through Enterprise Manager or by using the CREATEDATABASE T-SQL command. Only members of the sysadmin and dbcreator fixedserver roles or users who have been granted the CREATE DATABASE permission cancreate a new database.The following basic characteristics of the database have to be decided be<strong>for</strong>e creating adatabase: