Content overview

Conventional terms

Although dataxpress is based on SQL or uses it in the IBM i system, this documentation uses the traditional IBM i nomenclature (unlike in the relevant SQL literature), d.h. Files are referred to as not tables, fields not columns, and Sätze not rows.
The terms table, column, and row are used for the corresponding objects in Microsoft Excel.
The following terms are also used throughout:

Path program

A component of the software used to connect the PC to the IBM i system. The routing program (often referred to as Router) is supplied with Client/Access.
dataxpress has been using TCP/IP native as the connection to the IBM i since version 2.0. This connection is also referred to as routing program.

Client/Access

The software supplied by IBM that allows you to connect your PC´s to the IBM i system. Although you can usually use products from other manufacturers, the term Client/Access is always used for simplicity's sake.

Generator functions

Aggregate functions are functions that form a result of combining multiple columns, e.g. SUM(), MIN(), MAX(), AVG(), COUNT etc. With the exception of the COUNT function , which gives the number of Sätze from which a group was formed, aggregate functions can only be used with numeric fields.

Specific notes IBM i

dataxpress uses own server programs written in ILE/C which communicate with the PC via the SNA protocol APPC or via TCP/IP. These programs use SQL, native I/O routines and APIs to fulfill the client's requests.

security

dataxpress is, like any other IBM i program, subject to the object protection integrated in the OS/400 operating system, which cannot "be bypassed".
However, it is the nature of all query tools (such as ODBC drivers, QUERY/400, etc.).) that the data protection implemented by many users through menu control is overridden because the user practically has a "command line" when specifying his query.
In contrast to commercially available ODBC drivers, dataxpress "read only", i.e., all SQL statements except SELECT are rejected. A modification of the IBM i data by dataxpress is excluded.
dataxpress has the possibility to configure a user-specific EXIT program, which is called with each query and receives the name of the user and the file name as parameters. Based on this information, the EXIT program can perform additional authorization checks and allow or deny the query. For details, please refer to the IBM i Configuration.

section.

system load

dataxpress Queries load the system älike other query tools (OPNQRYF, QUERY/400 etc.). Incorrectly formulated queries can lead here and there to a situation where a relatively high system