February 2018 - users-list

MonetDB Connection drops issue on concurrency
by Sharma, Sreejith 12 Feb '18

12 Feb '18

Hi All, We have a situation where we are trying to emulate a scenario where we have multiple clients hitting into MonetDB instance in parallel, I mean with concurrency of for say 12 users. Queries are going through fine, however we notice connection drops in some cases and queries get cancelled. We assume, this happens when port is idle and when trying to reconnect there is a SQLConnect failure issues. If it's queries are firing uninterruptedly no issues spotted, if there is any idle situation the issue occurs. Can the "forward" - "redirect" option help here? If not, what other options? Regards, Sreejith

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Diacritic removal
by Roberto Cornacchia 09 Feb '18

09 Feb '18

Just wondering, before I do it myself, whether "normalizing" strings by removing diacritics is a feature that you guys would consider interesting to implement. (I am aware that results of this "normalization" can be unsatisfactory in some cases - I'm ok with most obvious cases covered) Basically, something like what iconv does here: $ echo "Ã é ç" | iconv -f UTF-8 -t ASCII//TRANSLIT A e c I can imagine that these above would be pretty easy to solve using the same hash lookup approach used for case conversion. These, however, are example that produce more than one symbol in output. So that would be a little more complicated. $ echo "æ ß" | iconv -f UTF-8 -t ASCII//TRANSLIT ae ss So I have two questions: 1) Is this something you guys (MonetDB developers) would be interested in implementing? 2) If not - in that case I'll give it a go myself, would you advise an approach similar to the case conversion or to use the iconv lib? Thanks for your input. Rboerto

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Install on Linux with no access to Internet
by ALEX OSSIPOV 08 Feb '18

08 Feb '18

I am trying to install MonetDB with client on the host without access to Internet. Are there any instructions to follow? Thanks Alex

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MonetDB Evaluation - Excessive slowness in a particular query
by Alfio Bettini 06 Feb '18

06 Feb '18

Hi all, we're testing MonetDB performances in order to understand if it could be possible to use it as data mart in our BI software. We're considering a set of queries executed in our test environment (CentOS 7, 32 GB RAM, 4 cpu). All the executed queries have quite good performances (between 10 and 45 seconds) except the following one that is taking several minutes in order to be executed: SELECT id, count(distinct value) FROM table GROUP BY id; The table contains 100 millions of data. It has about 130 columns (varchar, int, bigint, smallint, tinyint, timestamp, datetime). We have no BLOB/CLOB/Text types. The fields used in the query have these data types: id: int value: bigint Can you suggest us any optimizations in order to have this query run faster? Do you know some possible reasons why it's so slow? Kind Regards, Alfio Bettini The information contained in this message, together with any attachments, may be privileged and confidential and is intended for the use of the addressee(s) only. Any review, copying, use or distribution of this email by others (including any of its attachments) is strictly prohibited. If you are not the intended recipient, please destroy this email and its attachments and contact the sender immediately. This email was sent by EidosMedia SpA<http://www.eidosmedia.com>

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SQL Connect issues - ODBC Driver failure when idle situation
by Sharma, Sreejith 06 Feb '18

06 Feb '18

Hi All, Have a quick question - I have a situation where we are trying to emulate a scenario where we have multiple clients hitting into MonetDB instance in parallel, I mean with concurrency of for say 12 users. Queries are going through fine, however we notice some cases when a port/machine is idle and trying to reconnect we are finding SQLConnect failure issues. If it's queries are firing continuously it's fine, here if when some idle situation it may occur. Can the "forward" - redirect option help here? Regards, Sreejith

1 0

SQL Connect issues - ODBC Driver failure when idle situation
by Sharma, Sreejith 01 Feb '18

01 Feb '18

Hi All, Have a quick question - I have a situation where we are trying to emulate a scenario where we have multiple clients hitting into MonetDB instance in parallel, I mean with concurrency of for say 12 users. Queries are going through fine, however we notice some cases when a port/machine is idle and trying to reconnect we are finding SQLConnect failure issues. If it's queries are firing continuously it's fine, here if when some idle situation it may occur. Can the "forward" - redirect option help here? Regards, Sreejith

1 0