Chapter 1. What is Query for iSeries?

Query for iSeries is an IBM® licensed program and a decision support utility that can be used to obtain information from the DB2 Universal Database for iSeries database. It can obtain information from any database files that have been defined on the system using Operating System/400 (OS/400®) data description specifications (DDS), the OS/400 interactive data definition utility (IDDU), or DB2 UDB for iSeries Structured Query Language (SQL).

You use Query to select, arrange, and analyze information (data) stored in one or more database files to produce reports and other data files. You can create your own query definitions and then run them, you can run existing queries that you did not create, or you can even run a default query against a particular database file (using an unnamed query). You determine what data the query is to retrieve, the format of the report, and whether it should be displayed, printed, or sent to another database file.

You can use Query to obtain information from a single file or a combined set of up to 32 files. You can select all the fields, or a few of the fields and organize them as you want them to appear in the type of output chosen. You can have all records in the files included in the output, or you can select only a few to be included, using record selection tests. These and other functions are described in detail later.

This chapter begins by introducing basic information about Query, and then it introduces all the major tasks (such as creating, displaying, or running query) that can be done using Query.

Query for iSeries fundamentals

Several elements on your system organize and store information, or data, so that you and other system users can work with it to get the results that you need. The following topics introduce those elements, tell you about them and how they relate to you and Query, and direct you to other publications where you can find more information.

Files, fields, and record formats in Query for iSeries

Information, or data, is organized and stored on your system in various forms, primarily in objects called database files (usually referred to as just files). A file contains individual units of information, called records, that each contain related pieces of data. Each piece of information in a record is called a field, and how the fields are organized is defined in a record format (often just called a format).

When you run a query to produce a report, Query uses the files, fields, and record formats to get the information you want from the database, in the form of records, and uses those records to produce a query report.

For example, an employee name and address file named NAMEADDR might contain a group of records that identify one employee in each record (see Figure 1). Each record has several fields that contain the name and address of an employee. The fields in each record might have names like NAME, STREETADDR, CITY, STATE, and ZIPCODE. This order of the fields might be specified in a record format also named NAMEADDR.

NAME

STREETADDR

CITY

STATE

ZIPCODE

Susan P Gantner

907

Abbey Hwy

Mushroom Manor

OR

67891

Perry C Swenson

19821

Metro Hwy.

St. Paul

OR

67891

Matt F Thomas

961

S

19th Ave

Piney Island

OR

67890

Figure 1. Three Records in NAMEADDR File (Using Record Format NAMEADDR)

© Copyright IBM Corp. 2000, 2002

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IBM SC41-5210-04 manual What is Query for iSeries?, Query for iSeries fundamentals, State