Database setup

Before you install AS4 Microservice, you must configure the database that connects to AS4 Microservice.

When you set up your database, you must configure the following items to enable AS4 Microservice to use the database:

  • The database schema: If you are using the default schema that comes with the installation, run the IBM® Installation Manager and select the box for the Automatically create the schema in the specified data sources? field.
  • The page sizes for each data source. See Database page sizes.

Database page sizes

IBM requires the following minimum page sizes for each type of database:

Table 1. Database page sizes
Component Data source Page size (KB)
User interface MEGUI 32
Identity IdentityServerRepositoryDataSource 4
Communications MEGCommsDataSource 16 or greater
Infrastructure MEGInfrastructureDataSource 4

Oracle database block size

The block size (db_block_size) for an Oracle database depends on the value of the NLS_SEMANTICS_LENGTH parameter that you use to define table columns.

The value of NLS_SEMANTICS_LENGTH depends on the data that you are expecting. For example, if NLS_SEMANTICS_LENGTH='BYTE' and you are expecting multibyte character data where 2 bytes equals 1 character, you can store only 50 characters in a 100-byte space.

  • If NLS_SEMANTICS_LENGTH is set to the 'BYTE', the block size must be 8 KB (db_block_size=8192).
  • If NLS_SEMANTICS_LENGTH is set to the 'CHAR', the block size must be 16 KB (db_block_size=16384).

Oracle service IDs and service names

When you specify the connection information for an Oracle database during an installation of AS4 Microservice, you can specify one of the following database identifiers on the Data source configuration page of the Installation Manager:

  • The database name or the database service ID (SID) in the Database name field.
  • The database service name in the Service name field.

An SID is tied to a specific database instance. A service name can be shared between Oracle instances. For example, in an Oracle Real Application Clusters (RAC) installation, each Oracle cluster node has a unique SID, but shares one or more service names that might reach any or all of the RAC nodes.

The use of the service name simplifies the installation and operations of the database. The service name is then used as the identifier for all of the Oracle processes, including database and schema validation tests during the installation.

A service name also has these benefits:

  • You can use the service name to update all instances of a database in a database cluster.
  • You can use service names to identify different uses of the same database.

For more information, see the documentation on database SIDs and service names for your version of the Oracle database.

Row Versioning-Based Isolation Level (READ_COMMITTED_SNAPSHOT) for Microsoft SQL Server

This feature is available in Microsoft SQL Server 2005 and later versions, and can mitigate database locking during high database performance.
Important: When using Microsoft SQL Server 2005 and later versions with AS4 Microservice, you are required to use this feature.
This feature can help in the following ways:
  • Resolve concurrency issues such as excessive blocking
  • Reduce deadlocks
The following T-SQL statements enable the READ_COMMITTED_SNAPSHOT for a database:
  • ALTER DATABASE <DB NAME> SET ALLOW_SNAPSHOT_ISOLATION ON;
  • ALTER DATABASE <DB NAME> SET READ_COMMITTED_SNAPSHOT ON;

This snapshot option increases the number of inputs and outputs as well as the size of the tempdb. It is important to have tempdb on fast disks, as well as to have it sized according to your workload.

For more information about using and understanding snapshot isolation and row versioning, see the Microsoft Developer Network web site.