<< Click to Display Table of Contents >> Navigation:  The Vo2Ado RDD > Appendices > File structures > Index file structure

If you have not used functions in the index expression, the VO2ADO RDD will create an index on the server.

It also always stores the index information in an ADX file, which is a special kind of INI file.

This INI file has a section containing all the TAGS that are available in the index, and for each tag a section with the Index expression, and some additional index properties.

The Index expressions are stored in the VO index key format. A sample of such an ADX file is below

Just like with CDX files there is no limit to the number of tags/orders in an index file, but there may be a limit to the maximum number of indexes that you can create on the underlying table on the server.

Tag names are limited to 10 characters maximum, just like with the other RDD's

By default the file format for a compound index may looks like this:

 

[Tags]

ORDERDATE=1

ORDERID=2

 

[ORDERDATE]

IndexExpression=DTOS(ORDERDATE)

Descending=0

Unique=0

 

[ORDERID]

IndexExpression=ORDERID

Descending=1

Unique=1

 

A single tag index may look like this:

 

[Tags]

AU_LNAME=1

 

[AU_LNAME]

IndexExpression=UPPER(AU_LNAME)

Descending=0

Unique=0