The Database Services Interface

The Database Server (ladb)

The Database Server (ladb) is the main server engine. It analyzes and manages user requests, determines which database to access, and spawns database drivers. The ladb also notifies other servers of terminated database users.

Database (4GL) APIs

Presentation and application programs use Application Program Interfaces (APIs) provided by the Lawson system to communicate with the database. These APIs perform a set of functions such as finding a single record, summing each of three columns in a table, or deleting a set of records.

The Database Driver

The Database Server (ladb) communicates with the relational database management system (RDBMS) through database drivers. The driver translates Lawson 4GL Database APIs into native RDBMS SQL commands. The database driver is specific to the RDBMS you use. The following database driver is associated with the IBM DB2 server:

The Database Utilities

Several utilities are connected with the database driver to provide additional data access and management services. They are:

• verifyibm

  Compares Lawson dictionary descriptions to the expected translations in IBM DB2 to ensure the IBM DB2 database definitions match the Lawson dictionary.

• bldibmddl

  Generates SQL statements for creating or deleting selected tables, indexes, and stored procedures. The utility can operate on specific tables, all tables in a system code, or all tables in a data area.

• bldibmsec

  Duplicates Lawson table level security in the IBM DB2 database.

• ibmdu

  Calculates the space needed for an initial number of records in the database, using information found in the Lawson dictionary and both law_dba_table and law_dba_index.