Update indexes before form loads

[Mike Konoff]

Is there a way to update all indexes for a set just prior to a form for that set loading?

[Stan Mathews]

RE: Update indexes before form loads

Mike,

This should update the indexes of the primary table, which is how the set indexes are determined, I think.

"tbl".update_production_index()
Syntax:
"Tbl".update_production_index()
Description:
Updates all of the indexes in the production index of the table referenced by
"Tbl".
The production index is the index file with the same name as the table. The
production index is opened automatically when the table is opened.
Example:
'This script updates the indexs for the current table.
'------------------------------------------------------------------
tbl = table.current()
idx = tbl.update_production_index()
See Also:
"tbl".index_tag_add(), Table.index_create_begin(), Table.index_add(),
"tbl".index_create_end(), "index".update()

[Tom Cone Jr]

RE: Update indexes before form loads

Stan,
Is it necessary or advisable to open the tables in exclusive mode before updating the production index?

-- tom

[Stan Mathews]

RE: Update indexes before form loads

Tom,

Appreciate the suggestion. My first reply was really only dealing with the question of the method to update the indexes. (I'm sure you recognize it as cut-and-paste from the online documentation)

I would suggest exactly what you said, as well as error trapping to alert the user if the table(s) could not be opened in exclusive mode. As I understand it, if exclusive mode is not available and you don't check for that condition, the index update will not occur, but no error is returned.

Thanks,

Stan

[Tom Cone Jr]

RE: Update indexes before form loads

Yes, I recall bumping into this myself I believe. It was hard to spot because in a script which updated the indexes for several tables they all looked like they had run to completion, when in fact, only those which were successfully opened in exclusive mode actually got reindexed. I've since changed my error trapping to do a better job of calling these situations to my attention.

Thanks for your assistance.

-- tom

[Mike Konoff]

RE: Update indexes before form loads

Thanks for the advice guys.

I was able to do what I wanted by using .update_production_index().

Took me a while to figure out, but I got it to work. I've never really used xbasic, so it's a whole new ballgame for me.

I see that there I have a number of indexes while there is only one .cdx file. In A4 there was a seperate file for each index file. Are all indexes within the .cdx file in A5?

Thanks again,
Mike

[Lowell Wardlow]

RE: Update indexes before form loads

Mike - yes, all indexes are in the .cdx file.

About your original question - even though you CAN do what you ask, is it really a good idea ?

If you are in a multi-user environment, if another user has a form open for the same .dbf or set, you couldn't get access to the file, and if you were indexing, they, in turn,
couldn't get access.

Secondly, even if you are the only one on, or a single user system, it would seriously degrade performance to wait for a re-index every time you opened a form, unless you have pretty small files with few indexes.

Thirdly, I have always felt that is totaly unnecessary to
rebuild the indexes unless you have a reason to suspect that
there is a problem - for example, a power outage, or just getting wierd results. Indexes can get corrupted, and you should probably have a method to do them all at once, and
do a weekly or monthly maintenance run.

Just a thought.

Lowell :-)

[Stan Mathews]

RE: Update indexes before form loads

Unless you create a named index for some other purpose, yes.