October 2013 - users-list

How to take COLD RUNs Execution time
by Prashant Patel 07 Oct '13

07 Oct '13

as a part of my project, i have to check the performance of monetdb column-store database. I am very new to this technology, so i dont know where the monetdb caches its previous query results.. I want to know how can i take results for cold runs on monetdb ( i have tried closing monetdb client and server every time i fire a query , but doesnt seem to clear the cache and i always get hot runs result). I am using window 8 core i5 2.5GHz machine. so please can anyone help me regarding these.... suggestions are appreciated.. thanks in advance.. Prashant Rajkotiya M.tech. (ICT) DA-IICT ,Gandhinagar

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Window functions
by Hadley Wickham 05 Oct '13

05 Oct '13

Hi all, Does monetdb support window functions? I found https://www.monetdb.org/pipermail/users-list/2011-June/004992.html, which claims that OVER is supported, but: * I can't see where support is listed on http://www.monetdb.org/print/book/export/html/63 * I get errors when I try and use window functions: sql> SELECT *, MAX("AB") OVER (PARTITION BY "playerID") AS "_W4", MAX("G") OVER (PARTITION BY "playerID") FROM "Batting"; SELECT: function 'max' not found But that might be because I don't have the syntax right (but that query works in Postgres) Are there are any plans to add standard window functions like rank, ntile, lead, lag etc to monetdb? They are pretty useful for analysis. Hadley -- Chief Scientist, RStudio http://had.co.nz/

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new "too many digits" bug in SP-4
by Anthony Damico 03 Oct '13

03 Oct '13

this issue is new for SP-4 ..i have been using this syntax for a long time and never encountered this problem until the upgrade :( > dbGetQuery( db , "select ( sum( ( bene_sex_ident_cd = 1 ) ) ) / ( count( * ) ) as pct_male from x11" ) pct_male 1 0 > dbGetQuery( db , "select ( sum( ( bene_sex_ident_cd = 1 ) )*1.000 ) / ( count( * )*1.000 ) as pct_male from x11" ) Error in .local(conn, statement, ...) : Unable to execute statement 'select ( sum( ( bene_sex_ident_cd = 1 ) )*1.000 ) / ( count( * )*1.000 ) as pct_male from x11'. Server says 'too many digits (19 > 18)' [#22003]. > what diagnostics can i run for you to troubleshoot this? thanks!! :)

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Bug with fetching EXPLAIN results in Python DBAPI driver.
by Pete Hollobon 03 Oct '13

03 Oct '13

Hi, I spotted a bug in the Python DBAPI driver when fetching results from an EXPLAIN. >>> import monetdb.sql >>> db = monetdb.sql.connect(database="demo") >>> cursor = db.cursor() >>> cursor.execute("explain select count(*) from sys.tables") 31 >>> cursor.fetchone() Traceback (most recent call last): File "<stdin>", line 1, in <module> File "monetdb/sql/cursors.py", line 203, in fetchone result = self.__rows[self.rownumber - self.__offset] IndexError: list index out of range >>> I've logged a bug with patches for Python 2 and 3 here: http://bugs.monetdb.org/show_bug.cgi?id=3380 thanks, Pete.

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Static binary compilation
by Hassan, Ahmad 01 Oct '13

01 Oct '13

Hi, May be someone has tried compiling monetdb as a static binary please? I tried compiling the binary using -static flag but the resulting binary is still 'Dynamically linked' binary. I think it is due to glibc and dl libraries. If I pass libglibc.a and libdl.a statically then I get errors like: ============= /tmp/mserver5-rkIbiC.o: In function `mdlopen': /data/ahmad/test/MonetDB/gdk/gdk_posix.c:454: warning: Using 'dlopen' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking /usr/lib/x86_64-linux-gnu/libreadline.a(complete.o): In function `rl_username_completion_function': (.text+0x2bc9): warning: Using 'getpwent' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking ... /data/ahmad/test/MonetDB/common/stream/stream.c:1765: warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking ============= Does anyone know the workaround of creating static binary of monetdb executable please? Cheers, Ahmad

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