The test with SELECT * FROM PARTS was done local, not over the lan. It was done from the command prompt with SQLITE3.EXE. And data was just put into a file, noting more. But the table PARTS has 135 columns so 10 second is very god I think. Therefore I think the execution time of the slSel is 10 seconds. I will do some test with my method, doing slsel with limit 1000 and try to do updates from another program and see if there are any locking problems. I will report the result.
"Like this the database itself is locked only for a very short time." Short time in my aplication must be <0.5 second. I tested SELECT * FROM PARTS; with 53,000 rows, output to a file, about 10 seconds. So, if I change the LIMIT to 1000, the lock time will be less then 0.5 second and I will call the server with slsel about 50 times. How about that?