Fenrir The latter is the language that I use at work and the one that I use writing this tutorial. Each database has an associated database identifierwhich is a numerical value in the range 1 to 65, and a database namewhich is a character value with a maximum of 16 characters. A data field level number is a one- or two-digit number, from 01 to 07, used in conjunction with data field grouping. Intro — a few words of introduction To avoid confusion, keep in mind the two usages of the term descriptor throughout this document: If you like the article and you believe there should be more articles about Mainframes please clap a bitleave a comment or share this link wherever you want. Get updates Get updates.
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Group Field A group field is several consecutive data fields combined into one for efficient access and ease of reference. Defining a group field enables you to reference a series of data fields by using a group name.
A group field can also consist of other groups. In conjunction with grouping, you can assign level numbers 01 to 07 to define a group. Periodic Group Field A periodic group field is a group of data fields that repeat. A periodic group can be repeated up to times and can contain one or more elementary fields and multiple-value fields.
Groups can be nested, but periodic groups cannot. One periodic group cannot contain another. However, a record can have several periodic groups. A subfield is a data field defined from a portion of another data field. You use subfields for read operations only; they cannot be used for updating directly.
A superfield is a data field composed of several data fields, portions of fields, or combinations thereof. You use superfields for read operations only; they cannot be used for updating directly. You need to be aware of how the interface view engine maps multiple-value fields and periodic groups. That is, multiple-value field occurrences are mapped to multiple SAS variables, and periodic group occurrences are mapped to multiple SAS observations.
For retrievals, the results are straightforward. When updating, however, you need to keep in mind how the interface view engine maps multiple-value fields and periodic groups.
Each observation for his job titles and education data would display his last name. If you deleted an observation, for example, the one for Purdue, the deletion would not affect the last name or the job title data, but the Purdue observation would be gone. The standard format of a data field is specified with a one-character code shown next in the following table.
The standard length of a data field is specified in bytes; the maximum length is also given.
ADABAS ESSENTIALS PDF
Each database has an associated database identifier, which is a numerical value in the range1 to , and a database name, which is a character value with a maximum of 16characters. The Associator system file contains internal storage information that manages the data for the entire database. The Work Storage system file contains temporary work files. Output 2. The data fields are the vertical columnsof data.
Malrajas Get updates Get updates. In the next part of the tutorial we will learn about the syntax afabas the language and write our first program. Each database can consist of up to 5, logical files, depending on the device type. Programming languages on the mainframe As you can guess, to program Mainframe machines we usually use languages specially adapted for this. An ISN is the logical identifier for each record. The following output illustrates four data fields and seven logical records from an ADABAS file containing data about customers.