MonetDB is an open-source implementation of a column-oriented database. It is focused on analytical applications on a main memory resident database. MonetDB is a relational database and provides an SQL top-level interface. It is actively developed at CWI in Amsterdam, The Netherlands.
Questions tagged [monetdb]
441 questions
22
votes
6 answers
monetdb - anyone uses it in production?
I am very interested in using monetdb as a datamart, holding some huge data tables for querying and reporting
However, after some searching, I am unable to find any online posts / blogs regarding their use of Monetdb in any kind of production…
user1320615
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8
votes
2 answers
Is it worth trying MonetDB?
Has anyone had any experience with MonetDB? Currently, I have a MySQL database that is growing too large, and queries are getting too slow. According to column-oriented paradigm, insertions will be slower (which I don't mind at all), but data…
martincho
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7
votes
0 answers
Accessing MonetDBLite outside R
I created a big database using MonetDBLite in R and now I want to access the database outside R (e.g., with a general database GUI).
Is there a way to do this? I do not want to replicate the data as I still want to access it through R. I do not…
flippke
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- 2
7
votes
2 answers
Does RCHAR include READ_BYTES (proc//io)?
I read proc//io to measure the IO-activity of SQL-queries, where is the PID of the database server. I read the values before and after each query to compute the difference and get the number of bytes the request caused to be read and/or…
lupz
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6
votes
2 answers
How to have the list of table in a monetdb database?
In postgresql, one can have all tables names by running the following query
SELECT table_name FROM information_schema.tables WHERE table_schema='public';
Is there something similar in monetdb to have the list of tables ?
Fopa Léon Constantin
- 11,863
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5
votes
2 answers
Data storage for financial analysis
I am building system to analyze large quantities of financial data regarding securities trading prices. A large challenge in this is determining what storage method to use for the data given that the data will be in the 10's of terrabytes. There…
user396404
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5
votes
2 answers
Add new column to MonetDBLite table
I am trying to use R + MonetDB as a large-data analysis stack and am having trouble creating a new column and populating it with data from my analysis. Here is a toy example:
library(MonetDBLite)
library(DBI)
data(mtcars)
db <-…
Zelazny7
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5
votes
0 answers
MonetDB- Why doubling self-joins can cause query execution time to go from milliseconds to hours on the same data?
I'm running SQL queries on pretty simple table. Those tables model the RDF graph using the 'vertical partition' introduced here. Thus, they all have the following model where s is the 'subject' and o is the object.
CREATE TABLE a_table (BIGINT s,…
Fopa Léon Constantin
- 11,863
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5
votes
1 answer
min/max query with a where clause versus group by
Running MonetDB Database Server Toolkit v1.1 (Feb2013-SP6)
This query
select rowtype, min(zdate), max(zdate) , count(*)
from fdhista
group by rowtype
;
returns correct minimum and maximum dates for each rowtype.
rowtype L1 L2 L3
3 …
p99
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5
votes
1 answer
Is it possible to create a node.js module which uses c libraries for monetdb connection?
I am trying to connect monetdb with node.js. I have a simple (20 line) c program which can query moentdb using mapi libraries.
Can I use those libraries to build something(module/addon) for node.js which uses these libraries and connect to…
Gaurav
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4
votes
6 answers
To store images in SQL or not?
Generally, I had thought it was always better to store images in the filesystem and link to it via the database entry. However, I am trying to optimize my db design and am having a few questions.
My images are all really small thumbmails in black…
Brett
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4
votes
2 answers
How can I rename a table in MonetDB?
How can I rename a table in monetdb?
The typical SQL statement ALTER TABLE name RENAME TO new_name is not supported.
pic
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4
votes
1 answer
Is there a function in MonetDB that is equivalent to IF?
I need to do something like this in MonetDB:
select
If(value > 0, value, -1) as selected_value
from
table
In mysql, this means 'return value if value > 0, otherwise return -1.'
Is there an equivalent function to this in MonetDB?
And I am not…
Marina
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4
votes
1 answer
monetdb in the cloud, scalability, amazon s3
i have recently discovered MonetDB and i am evaluating it for an internal project, so probably my questions are from a really newbie point of view. Maybe someone could point me to a site and/or document where i could find more info (i haven't found…
Iosu S.
- 154
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4
votes
1 answer
How to convert a unix timestamp (INT) to monetdb timestamp ('YYYY-MM-DD HH:MM:SS') local time format
Q1: I want to convert a unix timestamp (INT) to monetdb timestamp ('YYYY-MM-DD HH:MM:SS') format
but it is giving me the GMT time not my actual time.
When I do
select (epoch(cast(current_timestamp as timestamp))-epoch(timestamp '2013-04-25…
Gaurav
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