Well, this is what I have discovered so far:
I left BLCKSZ as it was, but adjusted MAX_QUERY_SIZE to 65535, and ran make.
I tried to run a 50k query, and it worked; it took a while, but the results
were fine. So, as a temporary solution to this problem, you should be able
to set MAX_QUERY_SIZE up to what you require (don't go overboard, and please
let me know of any problems). However, make sure that you test it properly
first, because I didn't do extensive testing, just enough to make sure that
it didn't break immediately. Also, please remember that long queries
definitely impact the query processor, so long queries are not a great idea
for online sub-systems. They're not great for batch either, but at least
there you have a window to play with.
More news to come.....
>> > Troy wrote:
>> > >> Does Postgres have any limitations on
>> > >> the length of queries?
>> > >>
>> > >> E.g. is "select one,two,three,...thousand from
>> > where one = x and two is >> x and three is x and ...
>> thousand = x" legal?
>> > >>
>> > Yes, there is. It is set to BLCKSZ * 2, at least in 6.5.
>> BLCKSZ is
>> > normally 8192 bytes, so your query size will be 16k.
>> However, I'm busy
>> > working on it at the moment, to make it unlimited (i.e.:
>> limited by memory
>> > available).
>> > MikeA
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