Informix Version Property

Official Content
This documentation is valid for:

Tells GeneXus which Informix version is installed on the Database Server.

Values

7.31 to 8X
9 or higher

Default Value = 9 or higher(1)

(1) Informix 11 is supported as from GeneXus X.

Description

Every new version of the DBMS has new features that are used by GeneXus. This generates different SQL sentences or considers properties that can be applied to the new version.

Informix supports the management of Outer Join with a proprietary syntax (Informix-Extension Outer Joins). And from its 7.x engines, the syntax defined in the SQL-92 standard. The proprietary syntax is called "Informix-Extension Outer Joins", with a significant difference existing between both syntaxes, based on the order in which conditions are assessed.

To make this clear: when we have an Outer Join and want to apply a filter for an attribute in the extended table, Informix proprietary syntax first applies the filters of each table assessing conditions (minimizing the number of records returned), and then applies the JOINS, whereas with the ANSI syntax, the order in which conditions are assessed is well specified on the syntax itself (the Join condition is in one place and the overall conditions go in the associated Where section).

The idea in fact is for conditions assessments to be run post-join; that is: the ANSI syntax allows the specification of post-join filters, while the Informix proprietary syntax (Informix-Extension Outer Joins) returns different results and applies filters prior to joins (pre-join filters).

How to apply changes

Rebuild all objects

Scope

DBMS:  Informix

See Also

SQL server version property
Oracle version property
Informix Version Property
MySQL version property
DB2 UDB Version property