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Exactly 10 Seconds Delay during JDBC connect to MonetDB
by Robert Koch 22 Apr '15

22 Apr '15

Hi all, I'm using DBVisualizer to connect via JDBC to MonetDB. There is a delay of very exactly 10 seconds during the connection process. This only happens via JDBC. There are no DNS issues, since the connection is done via IP directly. Connection from the commandline of the server with mclient works perfectly. First step to get closer was to inspect the output of tcpdump. It seems to be on the side of MonetDB, since the last packet is the one sent to MonetDB (192.168.56.102) from my Windows Client (192.168.56.1). 09:33:24.663824 IP 192.168.56.1.57271 > 192.168.56.102.50000: Flags [.], ack 1, win 256, length 0 --- 10 soconds 09:33:34.676884 IP 192.168.56.102.50000 > 192.168.56.1.57271: Flags [P.], seq 1:3, ack 1, win 229, length 2 Additionally, DBVis ist connecting speedy with other databases (PostgreSQL) on the same server. Using following version: MonetDB 11.19.9 MonetDB Native Driver 2.14 (Liberica 20150123 based on MCL v1.11) I did not experience this problem in former versions of MonetDB. Any idea? Thank you.

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Creating an AWS AMI
by Maarten Sander 22 Apr '15

22 Apr '15

Hi everyone, Is there an easy way to create an AWS AMI running MonetDB? Perhaps someone maintains a Packer template? Regards, Maarten

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Strange syntax error when create trigger
by Caroptions Caroptions 21 Apr '15

21 Apr '15

Hi User-List, I am experiencing very strange behavior: CREATE TRIGGER marketdata.calc_sdate BEFORE INSERT ON marketdata.quotes FOR EACH ROW BEGIN ATOMIC -- select * from marketdata.quotes limit 1; END; ERROR: syntax error, unexpected '.', expecting WHILE in: "create trigger marketdata.calc_sdate before insert on marketdata." When I am creating trigger on table without schema it works fine. CREATE TRIGGER marketdata.calc_sdate BEFORE INSERT ON t1 ... Assuming t1 created without schema. All combination of " around schema and table, schema only, table only didn't help. Am I doing something wrong or this is the bug? Thanks,John

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More information about data loss in Bugzilla
by Luciano Sasso 20 Apr '15

20 Apr '15

I found this bug related to loss of data, is exactly what my bug, it was not clear in bugzilla if it was resolved or not, can tell me? I'm very insecure with MonetDB. https://www.monetdb.org/bugzilla/show_bug.cgi?id=3271 Att, -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br <http://www.gsgroup.com.br> --- Este email foi escaneado pelo Avast antivírus. http://www.avast.com

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More information about data loss
by Luciano Sasso 20 Apr '15

20 Apr '15

Hi, Some more details about data loss in MonetDB, I saw all that yours have commented, and also is aware that I am not with the latest version (update in ), but is a serious mistake in the previous version . Have a comment that said a data synchronization correction was made, has to do with the change or reorganization of data, even when it is only run queries? Will by defragmentation reasons (vacum PostgreSQL), or index creation, the data is changed / moved and in this case can be lost. The query for example is "select product from products where cod_product in (123,12434,33434)", only the data in this column (cod_product) were lost (went blank), and still only clinhas related codes on in. The only thing out of the ordinary has happened is that the ongoing connection was aborted, Pentaho was killed forced, aborting the connections, but the MonetDB service has stopped "stop MonetDB dw", which usually stopped, when start "moentdb start dw", rose correctly without errors, but took a long time to rise, very much, and then went to see the lost data. Att, -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br <http://www.gsgroup.com.br> --- Este email foi escaneado pelo Avast antivírus. http://www.avast.com

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MAL aggregate function difficulty
by Puthick Hok 20 Apr '15

20 Apr '15

Hi, I'm trying to define an aggregate function in MonetDB to concatenate rows in select group by (GROUP_CONCAT in MySQL). Postgres does not have this but there is an example to define this function. I'm starting to use monetdb from mysql thanks to MonetDB performance for large data sets. For some small tables, we have the feature to allow users to store small amount of custom data in rows and have a web service to convert rows into columns. We have this feature because we can do it in MySQL and Postgres using GROUP_CONCAT. I'm working on an open source breeding system which stores breeding data in MySQL, environment data in Postgres and now marker data in MonetDB in Australia. The system is called KDDart. Going back to my problem is that there is the same question with GROUP_CONCAT about 3 years ago. I have been googling and trying based on the information available for 2 days now. I have learnt how to define a MAL function and make it available in SQL mode by saving it in the autoload. However, when it comes to define and write a MAL aggregate function. I'm unable to find any step-by-step example. I could not start successfully with a simple aggregate solution. I google further that we a documentation on monetdb website about defining an aggregate function in R. I installed R and recompile my MonetDB source (MonetDB-11.19.9) on my openSuSe 12.2 with a pre-compiled R (R-base-2.15.1-1.1.4.x86_64). I followed the instruction to enable rintegration and compile successfully. R integration is loaded with mserver5 instruction. But when using monetdbd it says 'set: no such property: embedr'. I did bit of C debugging but I only got Segmentation fault. I don't know what you could do to help me out. I wish I could write the GROUP_CONCAT MAL function and being able to define it permanently in .mal file and being able to link it to the SQL. I hope you can help me out. Thanks in advance. Puthick

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MonetDB Cluster
by Luciano Sasso 17 Apr '15

17 Apr '15

Hello, I read all posts about cluster in MonetDB, but dont understand, I will make some specific quaestions, I think it will be more objective: 1- MonetDB makes automatic replication between nodes? 2- The writing is performed in a just node and this replicate to the other? 3. The reading can be done on any node? 4- There is a router that distributes queries between the nodes? 5- If a query from a client is very cost, this query can be distributed between nodes? 6- MonetDB makes sharding transparently? 7- How to funnel and multiplex ? Att, -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br <http://www.gsgroup.com.br> --- Este email foi escaneado pelo Avast antivírus. http://www.avast.com

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MonetDB vs Vertica CE
by Luciano Sasso 17 Apr '15

17 Apr '15

Hi, The team of staff this questioning me about using Vertica, but it has limitations on the CE version. Someone already used the Vertica has some advantage over MonetDB? -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br <http://www.gsgroup.com.br> --- Este email foi escaneado pelo Avast antivírus. http://www.avast.com

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MonetDB vs Vertica CE
by Luciano Sasso 17 Apr '15

17 Apr '15

Hi, thanks for awnsers. Precisely, I tried last year to deploy Vertical, but had trouble install and configure, since the MonetDB, was simply install and use, so do I use to this day with a database analytical about 30G, and 50 million records in the main table. I use Pentaho (Saiku) to explore the data, and also queries for creating dashboards. Now I pretty increase the volume of data, so that is posted another question about MonetDB clustered, it is the only thi still worries me, if I need to scalling. I dont think I still need something like HBase / Hadoop. Also have questioned me about using MongoDB, but from what I saw on MongoDB, needs a lot of programming to performance aggregations etc. with the MonetDB it is transparent. Today my data for analysis in MonetDB are fully denormalized not use model schema star. I see that many proposes the architecture with MongoDB for DW and Vertica or MonetDB, for analysis, but that think with volume that I have, I can use the MonetDB dw as well. I see there are many things about trying to force the use of Big data tools without really need it. Att, On 16/04/2015 10:38, users-list-request(a)monetdb.org wrote: > Send users-list mailing list submissions to > users-list(a)monetdb.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://www.monetdb.org/mailman/listinfo/users-list > or, via email, send a message with subject or body 'help' to > users-list-request(a)monetdb.org > > You can reach the person managing the list at > users-list-owner(a)monetdb.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of users-list digest..." > > > Today's Topics: > > 1. Re: MonetDB vs Vertica CE (Ruben Silva) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 16 Apr 2015 14:37:47 +0100 > From: Ruben Silva <ruben.silva(a)cortex-intelligence.com> > To: Communication channel for MonetDB users <users-list(a)monetdb.org> > Subject: Re: MonetDB vs Vertica CE > Message-ID: > <CAER5Ptm+M8e1B5r0bgXKnMrADGhW+ch6Wcdy5co1jw8b=CehCA(a)mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > Hello Luciano, > > I don't have a full grasp of the new stuff introduced into MonetDB in the > last year, but as far as I know there are still major differences between > the two systems for me the most important is scalability. Vertica has no > single point of failure when working as a cluster. However the CE version > is limited to three nodes, so scalability is also limited in that case. > > Vertica relies heavily on projections as a way to improve performance. If > your data model is relatively stable it is something fairly easy to use, > but if your data model changes at a high rate you will have a considerable > amount of additional work managing the projections. Also if you use many > projections they will hurt your DML statements performance. > > MonetDB feeds on CPU and has no boundaries for its appetite, consuming as > much resources as possible in order to respond to a single statement. That > can be very good or very bad, it depends on your use case. Vertica has > resource pools that are used to regulate the stuff (IO, Ram, CPU) that each > query is allowed to use. > > I don't know your use case (and that is crucial for a good advice), but if > you are considering a scenario where you have a single machine for the > database system, then go with MonetDB without any doubt. It is just faster > and simpler. > > Cumprimentos (Regards), > > 2015-04-16 14:04 GMT+01:00 Luciano Sasso <luciano(a)gsgroup.com.br>: > >> Hi, >> >> The team of staff this questioning me about using Vertica, but it has >> limitations on >> the CE version. Someone already used the Vertica has some advantage over >> MonetDB? >> >> -- >> Luciano Sasso Vieira >> Data Scientist & Solutions Architect >> >> luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 >> 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br >> >> >> ------------------------------ >> [image: Avast logo] <http://www.avast.com/> >> >> Este email foi escaneado pelo Avast antiv?rus. >> www.avast.com >> >> >> _______________________________________________ >> users-list mailing list >> users-list(a)monetdb.org >> https://www.monetdb.org/mailman/listinfo/users-list >> >> >

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MonetDB clustered
by Luciano Sasso 16 Apr '15

16 Apr '15

Hi, I have a question about MonetDB clustered 1- It only replicates data between nodes? 2- He replicates data between nodes doing sharding? 3- When a query is sent to the cluster, it is processed by one node just or distributed by several nodes? 4- Cluster is related to multiplex-funnel? Att, -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br <http://www.gsgroup.com.br> --- Este email foi escaneado pelo Avast antivírus. http://www.avast.com

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