RDBMS Configuration Variables

APPX_NO_END_CONSTRAINTS

Disables a performance optimization to use constraints on the upper range limit for record access. Do not set this variable unless requested by APPX Software, since the performance optimization is very useful.

Valid values: 1

Default value: not set

APPX_RDBMS_NDK

Superseded by the new RDBMS-related options that can be entered for FMS Groups and in File Specifications on the Database Management menu. These options are more flexible than environment variables and are the preferred choice. This information is included for completeness.

Determines how APPX creates RDBMS date key segments. Starting with release 3.5, you have a choice of how these date key segments are created. APPX_RDBMS_NDK controls the treatment of date key segments as follows:

Not Defined Date key fields are defined as ‘char’ and any NULL values are translated to or from blanks. This is a high performance option and also the default value.

APPX_RDBMS_NDK=NULL Date key fields are defined as ‘date null’. This is a low performance option, and many of the queries produced by APPX will ignore the defined indices.

APPX_RDBMS_NDK=MANDATORY Date key fields are defined as ‘date not null’. This is a high performance option, but no records with NULL values in a date key segment are stored.

APPX_RDBMS_NDK=some_value Date key fields are defined as ‘date not null’. Instead of storing NULL values, ‘some_value’ is stored when writing to the RDBMS and translated into NULL when reading from the RDBMS. This value should be a date constant which is valid in the RDBMS. For example, ‘some_value’ could be defined as ‘00010101000000’ to use midnight of January 1^st, 0001 AD as your NULL date.

Valid values: NULL, MANDATORY, or a string to be used in place of NULL

Default value: not set

APPX_SQL_BUFFER

Specifies the size of the SQL command buffer (in bytes) when communicating with an RDBMS. This is the area that will hold the actual SQL commands that are sent to the database server (an INSERT, complete with the entire record contents to be INSERTED, for example). This variable should never be set lower than 2048. You may need to increase it beyond the default value if you have a table containing many large fields.

Valid values: integers

Default value: 16384