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[MonetDB-users] select distinct ... where algorithm
by zack_pcd 13 Feb '12

13 Feb '12

I am seeing the following: select count(*) from f_sorted; +-----------+ | L7 | +===========+ | 102612097 | +-----------+ 1 tuple (0.988ms) select count(*) from f_sorted where yyyymm='201110'; +----------+ | L10 | +==========+ | 23505343 | +----------+ 1 tuple (1.0s) select count(distinct uuid) from f_sorted where yyyymm='201110'; +---------+ | L6 | +=========+ | 5941581 | +---------+ 1 tuple (23.8s) Very fast thus far! However: copy (select distinct(uuid) from f_sorted where yyyymm='201110') into '/home/user/filename' USING DELIMITERS ',','\n','"' NULL as 'null'; This has been running for hours and has yet to start writing to the file. I get this when I explain the query: +----------------------------------------------------------------------------------------+ | mal | +========================================================================================+ | function user.s5_3{autoCommit=true}():void; | | X_2 := sql.mvc(); | | X_22:bat[:oid,:str] := sql.bind(X_2,"sys","f_sorted","yyyymm",0); | | X_23 := algebra.uselect(X_22,"201110":str); | | X_20:bat[:oid,:str] := sql.bind(X_2,"sys","f_sorted","yyyymm",2); | | X_24 := algebra.kdifference(X_23,X_20); | | X_21 := algebra.uselect(X_20,"201110":str); | | X_25 := algebra.kunion(X_24,X_21); | | X_18:bat[:oid,:str] := sql.bind(X_2,"sys","f_sorted","yyyymm",1); | | X_19 := algebra.uselect(X_18,"201110":str); | | X_26 := algebra.kunion(X_25,X_19); | | X_16:bat[:oid,:oid] := sql.bind_dbat(X_2,"sys","f_sorted",1); | | X_17 := bat.reverse(X_16); | | X_27 := algebra.kdifference(X_26,X_17); | | X_28 := algebra.markT(X_27,0@0:oid); | | X_29 := bat.reverse(X_28); | | X_10:bat[:oid,:str] := sql.bind(X_2,"sys","f_sorted","uuid",0); | | X_8:bat[:oid,:str] := sql.bind(X_2,"sys","f_sorted","uuid",2); | | X_12 := algebra.kdifference(X_10,X_8); | | X_13 := algebra.kunion(X_12,X_8); | | X_5:bat[:oid,:str] := sql.bind(X_2,"sys","f_sorted","uuid",1); | | X_14 := algebra.kunion(X_13,X_5); | | X_30 := algebra.leftjoin(X_29,X_14); | | (ext44,grp42) := group.done(X_30); | | X_33 := bat.mirror(ext44); | | X_34 := algebra.leftjoin(X_33,X_30); | | X_35 := sql.resultSet(1,1,X_34); | | sql.rsColumn(X_35,"sys.f_sorted","uuid":str,"varchar",2048,0,X_34); | | X_43 := io.stdout(); | | sql.exportResult(X_43,X_35); | | end s5_3; | +----------------------------------------------------------------------------------------+ 31 tuples (1.350ms) Is it doing something wrong? I don't expect the query to take so long (hours) to produce the output, especially since the distinct count is also very fast. The copy-into *seems* to be irrelevant to the problem, but I decided to include it just in case, as that's how I am using the query. -- View this message in context: http://old.nabble.com/select-distinct-...-where-algorithm-tp33297578p332975… Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] False dependency
by Stathis Gkotsis 10 Feb '12

10 Feb '12

Hi all, trying to install: libmonetdb-client-dev_11.7.5-20120120_amd64.deb on Ubuntu 10.04, I see that there is a wrong dependency on libmonetdb-client1. Is there a way around this? Thank you.

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[MonetDB-users] re cycler_pipe and cracker_pipe
by zack_pcd 08 Feb '12

08 Feb '12

Is it possible to have a mix of these pipe's optimizers so you get the benefit of both? Or are these two pipes incompatible? (recycler_pipe and cracker_pipe) -- View this message in context: http://old.nabble.com/recycler_pipe-and-cracker_pipe-tp33282420p33282420.ht… Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] LIMIT clause not recognized in nested query in FROM clause
by Viktor Rosenfeld 07 Feb '12

07 Feb '12

Hi, it appears that clauses like LIMIT or OFFSET are not allowed if the query is used inside a FROM clause. The following query throws an error: SELECT * FROM ( SELECT id FROM corpus LIMIT 10 ) AS inner_table; The error message is: syntax error, unexpected LIMIT, expecting INTERSECT or EXCEPT or UNION or ')' in: "select * Cheers, Viktor

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[MonetDB-users] How can I execute SQL via mclient directly?
by bai dongli 02 Feb '12

02 Feb '12

Hi guys, I'm pretty new for Monetdb, As per the introduce of the online document, I have to type the password on the command line window when I want to execute SQL via the mclient program. It there a way like this which can be used in Mysql: "mysql --user --password databasename -e SQL" in monetdb? I didn't found the argument that can used for the "password" in mclient. Thanks, Tony

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[MonetDB-users] Can't drop "global temporary table" in SCHEMA tmp
by bai dongli 02 Feb '12

02 Feb '12

Hi guys, I got a problem when I trying to drop a global temporary table in my database, I got following errors: sql>drop table tmp.test; 42S02!DROP TABLE: no such table 'test' I got the same error as above when I trying to execute a "select" query on that table, It's so weird, cause the table "test" was been there: sql>\d TABLE tmp.test The even more weird things happened when I execute following command: sql>create global temporary table tmp.test(id int); operation successful (1.888ms) sql>\d TABLE tmp.test sql>\d test table tmp.test is not unique, corrupt catalog? sql>\d TABLE tmp.test sql>drop table tmp.test more>; operation successful (1.470ms) sql>\d TABLE tmp.test Please pay attention on this line "table tmp.test is not unique, corrupt catalog?". Do anybody can help me out of here? Thanks, Tony

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[MonetDB-users] Batch sql inserts in monetdb
by Federico Dayan 01 Feb '12

01 Feb '12

Hello all, I'm working in a project and we are planning to use monetdb. Our Data: We have around 15 millon users and 6,000 columns. Our Problem We need to be able to query specific log data. We use Hadoop to massage the data and create a sql file with sql inserts (around 15 millon insert with 3000 columns) Out Question Is it efficent to run a command like. By efficent I refe:. betweent 1 to 6 hours efficent, after that, a big problem. monetdb -u ....... < my_sql_insert.sql with 15 millon inserts and between 1000 to 3000 columns? (I'm not always going to create insert for the 6000 columns) could monetdb handle multiple of those command if a split the file. monetdb -u ....... < my_sql_insert_1.sql monetdb -u ....... < my_sql_insert_2.sql monetdb -u ....... < my_sql_insert_3.sql ... Is SQL COPY more efficient than a sql scrip file with inserts? BAT files is it significant faster ? I'm trying to avoid this approach since it seems a little bit obscue. any other suggestion? I'm not able to run all this test and get the info myself becuase I will not have a monetdb ready soon. Thank you very much and I would be glad to send back an email with the results I got and contribute in that way. Federico

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[MonetDB-users] size of table
by Pavel Stehule 30 Jan '12

30 Jan '12

Hello I can't to search in doc a way to get size of tables. Is there some function or statement how to do it? Thank you Pavel Stehule

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[MonetDB-users] Best backup strategy
by Sékine Coulibaly 27 Jan '12

27 Jan '12

Hi there, Thanks again for your last replies regarding the insertion into base. Using COPY INTO worked like a charm. A production deployment means : - Backup - High availability So my questions here, not addressed in the online docs are : - Regarding backup, is there a way to make a consistent backup (I mean putting the DB in a "backuping state", and save/archive the files) - To allow for high availability, can I use clusterization ? Can horizontal scalability be achieved through clusterization ? Thank you !

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[MonetDB-users] Announcement: New Dec2011 Feature release of MonetDB suite
by Sjoerd Mullender 26 Jan '12

26 Jan '12

The MonetDB team at CWI/MonetDB BV is pleased to announce the Dec2011 feature release of the MonetDB suite of programs. More information about MonetDB can be found on our website at http://www.monetdb.org/. For details on this release, please see the release notes at <http://www.monetdb.org/Downloads/ReleaseNotes>. As usual, the download location is <http://dev.monetdb.org/downloads/>. Dec 2011 feature release SQL * mclient: The csv output format can now also be of the form csv=c and csv+c where c is the column separator. The form with csv+ produces a single header line with column names. * Changed a bug where the sign() function returned the same type as its argument instead of always an INTEGER. * Added a fix for bug #2834, which caused weird (failing) behaviour with PreparedStatements. * Fixed a bug when using default values for interval columns. Bug 2877. * A bug was fixed where deleted rows weren't properly accounted for in all operations. This was bug 2882. * A bug was fixed which caused an update to an internal table to happen too soon. The bug could be observed on a multicore system with a query INSERT INTO t (SELECT * FROM t) when the table t is "large enough". This was bug 2883. Java Module * Implemented getMetaData() method of PreparedStatement. * Fixed an AssertionError for special results from e.g. EXPLAIN queries. * Fixed overflow error when batching large statements, bug #2952 * Resolved a concurrency problem where ResultSet's date-related getters could cause odd stack traces when used by multiple threads at the same time, bug #2950. * JDBC now implements JDBCv4.1 which makes it possible to be built with Java 7 and up. JDBCv4.1 is a maintenance release of JDBCv4, and hence can be compiled with Java 6, although the added methods obviously are not part of the java.sql interfaces. * SQLExceptions thrown now carry a SQLSTATE. Until the server starts sending correct SQLSTATEs for all errors, server originated errors without SQLSTATE are considered generic data exceptions (22000). * Fixed a bug where closing ResultSets and PreparedStatements could lead to errors on concurrent running queries using the same Connection due to a race condition. * Changed version scheme of JDBC driver and MCL jar to be more standard, from monetdb-X.Y-<thing>.jar to monetdb-<thing>-X.Y.jar, bug #2943 * The embedded monet instance capability of MonetConnection was removed. * Bump JDBC version to 2.0 (Liberica). JDBC now implements JDBCv4 which makes it possible to be built with Java 6 and up. Java 5 and before are no longer supported, and can use the 1.x releases of the driver. * INTERVAL columns are now treated as decimals, since they can have sub-second precision. Client Package * Fix making connections with stethoscope to hosts without monetdbd. Bug #2944. * Fixed some bugs in the PHP interface affecting the mapi_ping(), monetdb_insert_id() and auto_commit() functions. Bugs #2936, #2937, #2938. * ODBC: Fixed SQLNumResultCols and SQLDescribeCol to return useful information after a call to SQLPrepare and before any SQLExecute. * mclient: The exact interpretation of the -i (--interactive) option and the - filename argument have changed. The - filename argument means read from standard input and no longer implies that no \ interpretation is done on the input. Instead, \ interpretation is done if either standard input is a terminal, or if the -i option is given. The -i option no longer causes mclient to read from standard input. It only means to do \ interpretation when reading from standard input. Use the - filename argument to read from standard input. Note that if no -s option is specified and no filename arguments are present, mclient still reads from standard input. * ODBC: Improved internal query for SQLSpecialColumns. Before, the query returned all columns taking part in a PRIMARY KEY *and* all columns taking part in a UNIQUE constraint. Now it returns only one or the other set. * ODBC: The database name is now used as the catalog name throughout. Functions that return a catalog name return the database name, and functions that match on catalog name match it with the database name. * ODBC: Implemented an easier way to create a log file of interactions with the ODBC driver. You can now add a connection attribute "LOGFILE=filename" to the connection string parameter of SQLBrowseConnect and SQLDriverConnect, and to the relevant part of the Windows registry or odbc.ini file. This value is only used if there is no environment variable ODBCDEBUG. * Quoting of object names for mclient's \d command is now more flexible and consistent with standard SQL quoting rules, bug #2846. * ODBC: Implemented SQLColumnPrivileges function. * Install new program, mnc, which provides netcat functionality, but based on MonetDB's communication libraries * Report full URI to database instead of just database when available in mclient. * The time format of the timer output can now be controlled with an optional argument to the -i option. ms, s and m force the time to be formatted as milliseconds, seconds or minutes + seconds respectively. * ODBC: Implemented a workaround in SQLTables for bug 2908. * Small improvement to mclient's table rendering for tables without any rows. Previously, the column names in the header could be squeezed to very small widths, degrading readability. * Python DB API connect() function now supports PEP 249-style arguments user and host, bug #2901 * mclient now checks the result of encoding conversions using the iconv library. * Fixed a source of crashes in mclient when a query on the command line using the -s option is combined with input on standard input (e.g. in the construct mclient -s 'COPY INTO t FROM STDIN ...' < file.csv). * Fixed bug 2897 where slow (network) reads could cause blocks to not be fully read in one go, causing errors in the subsequent use of those blocks. With thanks to Rémy Chibois. * Fixed a bug in mclient where processing queries from files could result in ghost empty results to be reported in the output * Fixed Perl DBD rowcount for larger results, bug #2889 * Perl: We now distinguish properly between TABLE and GLOBAL TEMPORARY (the latter are recognized by being in the "tmp" schema). * Perl: fixed a bunch of syntax errors. This fixes bug 2884. With thanks to Rémy Chibois. * Perl: Fixed DBD::monetdb table_info and tabletype_info. This fixes bug 2885. With thanks to Rémy Chibois. * mclient: fix display of varchar columns with only NULL values. * Fixed a bug in mclient/msqldump where an internal error occurred during dump when there are GLOBAL TEMPORARY tables. MonetDB5 Server * A couple of memory leaks have been plugged. * Introduced new variable max_clients that allows to define how many concurrent connections are allowed to be made against the database. * mal_interpreter.mx Protect against concurrent exceptions If multiple parallel blocks access the exception variables and perform GDKfree on old messages, then we may enter a case that one thread attempts a second free. Simple lock-based protection is the first line of defense. * bpm and partitions have been moved to the attic. It is replaced by the partition optimizer, still under construction. * The MAL debugger next/step operations semantics have been fixed. The profiler also now clearly shows entrance/exit of a MAL function. * The dataflow optimizer uses a less strict side-effect test for BAT new operations and better recognizes trivial plans. * Fixed a problem where MAL variables weren't properly cleared before reuse of the data strucutre. This problem could cause the data flow scheduler to generate dependencies between instructions that didn't actually exist, which in turn could cause circular dependencies among instructions with deadlock as a result. Bugs 2865 and 2888. Merovingian * Fixed crash in monetdb when an invalid property was retrieved using the get command, bug #2953. * monetdb get output is now grouped by database instead of by property * Unlike in previous releases, 'monetdbd get mserver' now returns the path to the mserver5 binary only for dbfarms that have a running monetdbd, instead of only for those that are not served by a monetdbd. * Add nclients property that controls the maximum number of concurrent clients allowed to access the database * Starting monetdbd without any arguments or without dbfarm is no longer supported. A dbfarm now must be provided for each command. * The control passphrase has been turned into a hash of the password, for a more stronger authorisation model as used by mclients. On upgrade, any existing passphrase is converted to the hashed version of the passphrase. * The monetdbd controlport option has been removed in favour of a boolean control option. On upgrade, when controlport was set to a non-zero value and a passphrase was set, control is set to true, or false otherwise. * The monetdbd discoveryport option has been removed in favour of a boolean discovery option. On upgrade, when discoveryport was set to a non-zero value, discovery is set to true, or false otherwise. * Fixed a bug where monetdbd's socket files from /tmp were removed when a second monetdbd was attempted to be started using the same port. * Resolved problem where monetdbd would terminate abnormally when databases named 'control', 'discovery' or 'merovingian' were stopped. * monetdbd get status now also reports the version of the running monetdbd * Improved response time of 'monetdb start' when the database fails to start. * Fixed a bug in monetdbd where starting a failing database could incorrectly be reported as a 'running but dead' database. * To avoid confusion, all occurrences of merovingian were changed into monetdbd for error messages sent to a client. MonetDB Common * Fixed memory detection on 32-bits Solaris systems with more memory than can be addressed in 32-bits mode, bug #2935 Bug Fixes

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