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<DIV>Hi, all,</DIV>
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<DIV>I read from the mailing list a few days ago about using mnesia:dirty_update_counter() to generate key. I want to use this feature as well, so I have come up with this little test script:</DIV>
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<DIV>-module(db_seq).</DIV>
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<DIV>-record(counter, {tab, key, value}).</DIV>
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<DIV>-export([init_mnesia_db/0, get_next_seq/1, test/0, setup/0]).</DIV>
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<DIV>-define(SERVER, ?MODULE).</DIV>
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<DIV>get_next_seq(Key) -><BR> mnesia:dirty_update_counter(counter, Key, 1).</DIV>
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<DIV>setup() -><BR> mnesia:create_schema([node()]),<BR> mnesia:start(),<BR> mnesia:create_table(counter, [{disc_copies, [node()]},<BR> {type, ordered_set},<BR> {attributes, record_info(fields, counter)}]),<BR> mnesia:stop().<BR> </DIV>
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<DIV>test() -><BR> mnesia:start(),<BR> mnesia:wait_for_tables([counter], 20000),<BR> mnesia:dirty_update_counter(counter, a, 1).</DIV>
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<DIV>====</DIV>
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<DIV>I fired up erl with this command line "erl -mnesia dir local". Then I executed db_seq:setup() in order to create the schema and table.</DIV>
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<DIV>Then I run db_seq:test() in order to obtain an integer value, which failed with this message:</DIV>
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<DIV>6> db_seq:test().<BR>** exited: {aborted,{combine_error,counter,update_counter}} **<BR></DIV>
<DIV>So, what is a "combine_error"? What is the best way to find out the meaning of these error messages (apart from asking the question in mailing list)? Is reading the source code the only way? (Don't get me wrong, I do not mind reading them, but really would like to learn how you guys decipher this kind of error message normally during development...)</DIV>
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<DIV>Cheers, Anthony</DIV>
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