October 2017 - users-list

Proper syntax for a windowing function
by Omri Schwarz 25 Oct '17

25 Oct '17

Hi, all. I'm trying to figure out the proper syntax for queries such as a moving average over a window in MonetDB. THis works: sql>select avg(energy) from TABLENAME; +--------------------------+ | L3 | +==========================+ | 658.5049567388747 | +--------------------------+ This fails: select avg(energy) OVER () from TABLENAME; SELECT: function 'avg' not found (Welcome to mclient, the MonetDB/SQL interactive terminal (Jul2017-SP1) Database: MonetDB v11.27.5 (Jul2017-SP1), 'mapi:monetdb://SERVER2:50000/scada' ) How do I write such a query? Many thanks.

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Transaction Replication Question
by Sharma, Sreejith 25 Oct '17

25 Oct '17

All, I wanted to have "Transaction Replication" setup for getting an load balanced environment. It's mentioned in the documentation that below property needs to be setup for replication or shipping of the transaction log. How and where should I setup this? Is there anything else I should keep in mind for transaction replication? gdk_keep_persisted_log_files gdk_shared_logdir gdk_shared_drift_threshold Also, I wanted to know if we can have similar approach as below. Can we have different tables that are part of the same schema from different disks/mounts in MonetDB? Table 1 from Mount X Table 2 from Mount Y Regards, Sreejith

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Yacc bug in sql_parser.y ?
by Omri Schwarz 24 Oct '17

24 Oct '17

Hi, all. Still trying to get rolling averages out of my MonetDB database, and I ran into this: Line 3954 of sql_parser.y, window_frame_end: UNBOUNDED FOLLOWING { $$ = _symbol_create_int(SQL_FRAME, -1); } | window_frame_following { $$ = $1; } | CURRENT ROW { $$ = _symbol_create_int(SQL_FRAME, 0); } ; window_frame_following: value_exp PRECEDING { $$ = $1; } ; Should that not be "value_exp FOLLOWING "?

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RE: Transaction Replication Question - how to setup gdk_keep_persisted_log_files?
by Sharma, Sreejith 24 Oct '17

24 Oct '17

Also, below parameters. gdk_shared_logdir gdk_shared_drift_threshold From: Sharma, Sreejith Sent: Tuesday, October 24, 2017 4:01 PM To: Communication channel for MonetDB users Subject: Transaction Replication Question - how to setup gdk_keep_persisted_log_files? All, I wanted to have "Transaction Replication" setup for getting an load balanced environment. It's mentioned in the documentation that below property needs to be setup for replication or shipping of the transaction log. How and where should I setup this? Is there anything else I should keep in mind for transaction replication? gdk_keep_persisted_log_files Regards, Sreejith

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Transaction Replication Question - how to setup gdk_keep_persisted_log_files?
by Sharma, Sreejith 24 Oct '17

24 Oct '17

All, I wanted to have "Transaction Replication" setup for getting an load balanced environment. It's mentioned in the documentation that below property needs to be setup for replication or shipping of the transaction log. How and where should I setup this? Is there anything else I should keep in mind for transaction replication? gdk_keep_persisted_log_files Regards, Sreejith

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IMPORTANT: serious possibility for database corruption
by Sjoerd Mullender 23 Oct '17

23 Oct '17

We just found (and fixed) a serious problem in the Jul2017 releases that can result in database corruption. So far we have only seen the corruption occur after a database (mserver5) restart. We have not yet seen a problem with a server that continues running (but unfortunately no guarantees). We will create a new release candidate with this bug fixed as soon as possible (that will be version 11.27.9, i.e. anything in the 11.27.X series older than this is affected). Currently known work around is to *not* restart the server, but keep it running, and creating a dump of the database using msqldump. This dump will then have to be restored into a fresh database in a server that is not affected by the bug (Dec2016 release or the upcoming Jul2017-SP2). -- Sjoerd Mullender

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Problem in installation
by Amit Ambekar 23 Oct '17

23 Oct '17

Hi Stefan, I had installed monetdb and now wanted to start mclient. So first i started Mserver5.bat and then when i click on mclient.bat that time "api-ms-win-crt-runtime-l1-1-0.dll is missing issue" this error is coming in alert box. Is monetdb is only usefull for windows server 2003,vista and Windows 7 or it can be used with Windows 2012 server also? On Monday 23 October 2017 03:30 PM, 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. Why does corr(int,int) return int? (Stefan Manegold) > 2. Re: Why does corr(int,int) return int? (Anthony Damico) > 3. Problem in installation (Amit Ambekar) > 4. Re: Why does corr(int,int) return int? (Stefan Manegold) > 5. Re: Problem in installation (Stefan Manegold) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 22 Oct 2017 19:48:27 +0200 (CEST) > From: Stefan Manegold <Stefan.Manegold(a)cwi.nl> > To: Communication channel for MonetDB users <users-list(a)monetdb.org> > Subject: Why does corr(int,int) return int? > Message-ID: <1997044866.6459538.1508694507470.JavaMail.zimbra(a)cwi.nl> > Content-Type: text/plain; charset=utf-8 > > > Hi, > > could some one possible explain to me > why the MonetDB corr() aggregate function, > that IMHO is supposed to calculate the correlation between two attributes, > does return the same type as (the larger of) its input type(s)? > > IMHO the correlation between two attributes (or (samples of) random variables > is a factional value between -1 and 1. > > Consequently, MonetDB corr() on two integer columns returns an integer results, > i.e., one of {-1,0,1} ... > > Shouldn't corr() --- much like avg(), var_pop(), var_samp(), stddev_samp(), stddev_pop() > always return type double ? > > Thanks! > > Best, > Stefan > -- Amit Ambekar Technology Associate Office: Ist floor, Poddar Chambers, Mathruradas Mill Compound, Lower Parel, Mumbai 400013 | Landline: +91 22 43470408 Cell: +91-7741823310 | Email: amit(a)g-square.in| Website: www.g-square.in cid:image003.png@01D2A947.80D76E60

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Problem in windows OS
by Amit Ambekar 23 Oct '17

23 Oct '17

Hi, I am using monetdb since long time with linux OS, i just tried it with Windows 7 OS. But in windows after shut down machine, database is crashing. I am not able to use any query in mclient now for that databases. What is problem ?

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Why does corr(int,int) return int?
by Stefan Manegold 23 Oct '17

23 Oct '17

Hi, could some one possible explain to me why the MonetDB corr() aggregate function, that IMHO is supposed to calculate the correlation between two attributes, does return the same type as (the larger of) its input type(s)? IMHO the correlation between two attributes (or (samples of) random variables is a factional value between -1 and 1. Consequently, MonetDB corr() on two integer columns returns an integer results, i.e., one of {-1,0,1} ... Shouldn't corr() --- much like avg(), var_pop(), var_samp(), stddev_samp(), stddev_pop() always return type double ? Thanks! Best, Stefan -- | Stefan.Manegold(a)CWI.nl | DB Architectures (DA) | | www.CWI.nl/~manegold/ | Science Park 123 (L321) | | +31 (0)20 592-4212 | 1098 XG Amsterdam (NL) |

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Is there kind of tablespace concepts?
by Sharma, Sreejith 18 Oct '17

18 Oct '17

Hi All, Is there any possibility of retrieving the same table from 2 different sources (as similar to 2 tablespaces)? Regards, Sreejith

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