I tried something amusing that seems to work but I have not tested its
speed.

0 - select...
1 - close table B
2 - delete from selection (A must be editable, C is not required)

Jacques Paris
e-mail  [EMAIL PROTECTED]
MapBasic-MapInfo support  http://www.paris-pc-gis.com

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: June 27, 2002 09:40
To: [EMAIL PROTECTED];
[email protected]
Cc: [EMAIL PROTECTED]
Subject: MI-L MapBasic: deleting a selection

Hi,

Situation: My query in MapBasic selects all records from table A that
intersect
table B. The query result C is saved as a MapInfo table. Now I want to
delete
all records from table A that were selected initially. Because for the
initial
query two tables are used, the selected records from table A cannot be
deleted
("cannot delete from a view"). Therefore, I select all records from A that
have
a same identifier as the records in table C, using a nested query.

Select * from A, B Where A.Obj Intersects B.Obj Into C
...save table C and open it...
Select * from A Where ID = Any (Select ID from C) Into qryDelete
Delete from qryDelete

Problem: this approach is awfully slow. Removing 500 records from 5000,
takes
about two minutes.

Solution: ?

Does anyone know a faster approach.

Best regards,

Ren� Bruinink

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