Hi, > Last time I checked, SELECT ... FOR UPDATE ensures tables get locked, but does not specify what in what order (for multi-table queries).
Yes, that's why I wrote: "you could lock one table at a time". Please note the "one table at a time". Regards, Thomas On Mon, May 20, 2013 at 6:55 PM, cowwoc <[email protected]> wrote: > Thomas (and Noel), > > Last time I checked, SELECT ... FOR UPDATE ensures tables get locked, > but does not specify what in what order (for multi-table queries). Whether > for H2 or SQL as a whole, locking order for multiple tables seems to be > treated as an implementation detail. Again, this is a guess based on what > I've experienced so far. Please let me know if I'm wrong. > > After much consideration, I think I will give up and simply push the > problem out to the client: http://stackoverflow.com/q/16628713/14731 ... > Not ideal, but (I think) it'll work. > > Gili > > > On 20/05/2013 9:34 AM, Thomas Mueller wrote: > > Hi, > > Yes, if it's a problem, you could lock one table at a time (using > "select ... for update"). > > Regards, > Thomas > > On 20/05/2013 9:29 AM, Noel Grandin wrote: > > > It's basically a non-problem. > In 20 years of database programming, I've never seen it myself. > For people who did see it, the recommended approach was to lock the data > by hand for the relevant queries, using LOCK TABLE or FOR UPDATE clauses. > > > > On Sat, May 18, 2013 at 1:58 AM, Gili <[email protected]> wrote: > >> Hi, >> >> I wanted to get your opinion regarding >> http://stackoverflow.com/a/112256/14731 >> >> Is it fair to say that database deadlocks are not preventable: >> >> 1. Using portable SQL, since the SQL standard does not specify lock >> ordering; >> 2. Using database-specific SQL code, because the execution plan of a >> database might change over time. >> >> Thank you, >> Gili >> -- >> You received this message because you are subscribed to the Google Groups >> "H2 Database" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/h2-database?hl=en. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> > > -- > You received this message because you are subscribed to a topic in the > Google Groups "H2 Database" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/h2-database/cwXlxLOdr4A/unsubscribe?hl=en > . > To unsubscribe from this group and all its topics, send an email to > [email protected]. > > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/h2-database?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > > > -- > You received this message because you are subscribed to the Google Groups > "H2 Database" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/h2-database?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
