Editing ADABAS (section)

==Adabas data model==
Adabas is an [[acronym]] for Adaptable Data Base System<ref>{{Harvnb| Pratt | Adamski | 1987 |p=471 |Ref=Pratt&Adamski1987}}</ref> (originally written in all caps; today only the initial cap is used for the product name).

Adabas is an [[inverted list]] data base, with the following characteristics or terminology:
* Works with tables (referred to as files) and rows (referred to as records) as the major organizational units.
* Columns (referred to as fields) are components of rows.
* No embedded [[SQL]] engine. SQL access via the Adabas SQL Gateway was introduced through an acquired company, CONNX, in 2004.<ref>{{cite web |url=http://www.connx.com/databases/adabas-db.php |title=CONNX for Adabas |website=CONNX Solutions |access-date=2017-09-01}}</ref> It provides ODBC, JDBC, and OLE DB access to Adabas and enables SQL access to Adabas using [[COBOL]] programs.
* Search facilities may use [[Index (database)|indexed fields]], non-indexed fields, or both.
* Does not natively enforce [[referential integrity]] constraints, and parent–child relations must be maintained by application code.
* Supports two methods of [[denormalization]]: repeating groups in a record ("periodic groups") and multiple value fields in a record ("multi-value fields").

Adabas is typically used in applications that require high volumes of [[data processing]] or in high-transaction [[OLAP|online analytical processing]] environments.<ref>{{cite web |title=WHAT IS ADABAS? |url=https://archive.sap.com/discussions/thread/577971}}</ref>

Adabas access is normally through Natural modules using one of several Natural statements including READ, FIND, and HISTOGRAM. These statements generate additional commands, under the covers, like open and close file. Adabas data can also be retrieved via direct calls.{{citation needed|date=August 2018}}

=== Example of Natural program running against Adabas ===
<syntaxhighlight lang="cobolfree">
FIND EMPLOYEE WITH NAME = 'JONES' OR = 'BAKER'
 AND CITY = 'BOSTON' THRU 'NEW YORK'
 AND CITY NE 'CHAPEL HILL'
 SORTED BY NAME
 WHERE SALARY  < 28000
  DISPLAY NAME FIRST-NAME CITY SALARY
END-FIND 
END
</syntaxhighlight>

In the above program, the search criteria specified in the <code>WITH</code> clause is processed by Adabas, whereas the additional filtering indicated by the <code>WHERE</code> clause is performed by Natural.

Output of program:
<syntaxhighlight lang="output">
NAME  FIRST-NAME CITY      SALARY 
---------------------------------
BAKER PAULINE    DERBY     4450
JONES MARTHA     KALAMAZOO 21000
JONES KEVIN      DERBY     7000
</syntaxhighlight>