On Fri, 2005-07-15 at 16:41 +0530, Roushan Ali wrote: > Hello all, > Can we use single sqlite_open handle(global) across threads( > if all database operations are serialized by using semaphore) ? Please > help. >
Opening a database connection in one thread and using it in another will work on some operating systems but not on others. You are advised not to do it. See http://www.sqlite.org/cvstrac/tktview?tn=1272 and http://www.sqlite.org/cvstrac/chngview?cn=2521. Actually, this seems like a good opportunity to repeat my oft-ignored advice to not use more than one thread in a single address space. If you need multiple threads, create multiple processes. This has nothing to do with SQLite = it is just good programming advice. I have worked on countless multi- threaded programs over the years, and I have yet to see a single one that didn't contain subtle, hard to reproduce, and very hard to troubleshoot bugs related to threading issues. I am constantly amazed at the prevailing idea (exemplified by Java) that software should be strongly typed and should not use goto statement or pointers - all in the name of reducing bugs - but that it is OK to use multiple threads within the same address space. Strong typing helps prevent only bugs that are trivially easy to locate and fix. The use of goto statements and pointers likewise results in deterministic problems that are easy to test for and relatively easy to track down and correct. But threading bugs tend to manifest themselves as timing-dependent glitches and lock-ups that are hardware and platform dependent, that never happen the same way twice, and that only appear for customers after deployment and never in a testing environment. -- D. Richard Hipp <[EMAIL PROTECTED]>
