Hello, Thank you for your answers. I will set LOCK_MODE to 3.
On Friday, February 15, 2013 11:54:29 AM UTC+3, Thomas Mueller wrote: > > Hi, > > The setting LOCK_MODE is persistent, as documented: > http://h2database.com/html/grammar.html#set_lock_mode - so the setting is > stored in the database, and the next time you open it the same mode is > used. So you only need to set it to 3 once (not each time). > > For import, CREATE TABLE AS SELECT has the same effect than LOG=0. So if > you use CREATE TABLE AS SELECT then you don't need to use LOG=0. LOG=0 will > only improve performance if you use INSERT INTO .. SELECT. > > Regards, > Thomas > > > > On Mon, Feb 11, 2013 at 6:02 PM, Ivan Staskov > <[email protected]<javascript:> > > wrote: > >> Hi, >> >> I create H2DB as a file and import the huge amount of data with Fast >> Database Import options: >> http://www.h2database.com/html/performance.html#fast_import. >> "LOG=0;CACHE_SIZE=65536;LOCK_MODE=0;". >> After import of data I open connections with 'MULTI_THREADED=TRUE' option >> only for reading data. >> It worked in the one of the old version of h2DB ("h2-1.2.145.jar"), I >> didn't get any problem. >> >> Now, I'm using h2-1.3.164.jar. And my attempt to open connection with >> 'MULTI_THREADED=TRUE' option leads to Exception: >> > Cannot change the setting "LOCK_MODE=0 & MULTI_THREADED" when the >> database is already open; SQL statement: >> > SET MULTI_THREADED TRUE [90133-164] >> >> In the documentation for Fast Database Import I see: "Most of those >> options are not recommended for regular use, that means you need to reset >> them after use." >> Additionally I see that the same problems was already discussed here: >> https://groups.google.com/forum/?fromgroups=#!topic/h2-database/ZOw4ot12dRE >> >> My questions are: >> - How can I rest the options of Fast Database Import that stored in the >> h2db file? >> - Should I always set 'MULTI_THREADED=TRUE:LOCK_MODE=3' options (explicit >> set the 'default' option for LOCK_MODE)? >> It seems that it solve my problems, at least Exception is not thrown. Is >> it correct solution? >> - Why H2DB doesn't release the options of the old connections, perhaps >> exists some configuration to enable this mode? >> >> Thank you. >> Ivan >> >> -- >> 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] <javascript:>. >> To post to this group, send email to [email protected]<javascript:> >> . >> 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.
