April 2011 - users-list

[MonetDB-users] Proofreading your professional documents
by Richard Hounslow 24 Feb '24

24 Feb '24

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[MonetDB-users] MonetDB JDBC 1.9 question
by Charalampos Nikolaou 23 Feb '12

23 Feb '12

Hi, I am getting some strange exceptions using MonetDB JDBC 1.8/1.9, and I decided to look into the code. While inspecting the code I came across these strange lines in MonetConnection.executeQuery(String[] templ, String query) method (http://dev.monetdb.org/hg/MonetDB/file/718da8ca0a1a/java/src/nl/cwi/monetdb…). In my case, these lines are executed for sure when doing a batch insert. So, suppose that the batch contains the following commands (as constructed by the MonetStatement.executeBatch() method): exec 1(1, 957339737330229055); exec 1(2, 278262503670654331); exec 1(805306369, 3763943296910752235) The lines in question take the above commands as a string, prepend a 's' character and append a ';' at the end. The resulting commands, which are written in the server's socket, are the following: sexec 1(1, 957339737330229055); exec 1(2, 278262503670654331); exec 1(805306369, 3763943296910752235); First of all, I am not familiar with the internals of JDBC drivers. Taking this into account, is this what it should be? From a symmetric point of view, I would assume that the correct would be the following: sexec 1(1, 957339737330229055); sexec 1(2, 278262503670654331); sexec 1(805306369, 3763943296910752235); That is, it should prepend a 's' character before an exec command. Last, are these exec commands (with or without a prepending 's') specific to MonetDB? In either case, is there any documentation to get familiar with their meaning? Thanks a lot, Babis

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[MonetDB-users] protocol violation: unexpected line in data block
by tangray 27 Dec '11

27 Dec '11

the whole log file : RD 1298855541531: read final block: 57 bytes RX 1298855541531: onxRWd3Yv:mserver:9:RIPEMD160,SHA256,SHA1,MD5:LIT:SHA512: RD 1298855541531: inserting prompt TD 1298855541531: write final block: 92 bytes TX 1298855541531: BIG:risk:{SHA256}01fa94fefcadb5918473e49aaa8e425538f8d40960b2d649348cb17c599031ae:sql:krisk: RD 1298855541546: read final block: 0 bytes RX 1298855541546: RD 1298855541546: inserting prompt TD 1298855541546: write final block: 48 bytes TX 1298855541546: sSET TIME ZONE INTERVAL '+08:00' HOUR TO MINUTE; RD 1298855541546: read final block: 0 bytes RX 1298855541546: RD 1298855541546: inserting prompt TD 1298855541546: write final block: 15 bytes TX 1298855541546: Xreply_size 250 RD 1298855541546: read final block: 0 bytes RX 1298855541546: RD 1298855541546: inserting prompt TD 1298855541546: write final block: 46 bytes TX 1298855541546: sSELECT "name", "value" FROM sys.env() as env; RD 1298855541546: read final block: 4246 bytes RX 1298855541546: &1 0 46 2 46 % .env, .env # table_name % name, value # name % varchar, varchar # type % 18, 203 # length [ "gdk_arch", "32biti686-pc-win32" ] [ "gdk_version", "1.40.3" ] [ "prefix", "D:\\Program Files\\MonetDB\\MonetDB5" ] [ "exec_prefix", "D:\\Program Files\\MonetDB\\MonetDB5" ] [ "gdk_dbname", "krisk" ] [ "gdk_dbfarm", "C:\\Documents and Settings\\swordtan\\Application Data\\MonetDB5\\dbfarm" ] [ "gdk_debug", "0" ] [ "gdk_alloc_map", "no" ] [ "gdk_vmtrim", "yes" ] [ "monet_admin", "adm" ] [ "monet_prompt", ">" ] [ "monet_welcome", "yes" ] [ "monet_mod_path", "D:\\Program Files\\MonetDB\\MonetDB5\\lib\\MonetDB5;D:\\Program Files\\MonetDB\\MonetDB5\\lib\\MonetDB5\\lib;D:\\Program Files\\MonetDB\\MonetDB5\\lib\\MonetDB5\\bin" ] [ "monet_daemon", "no" ] [ "host", "localhost" ] [ "mapi_port", "50000" ] [ "mapi_clients", "2" ] [ "mapi_open", "true" ] [ "mapi_autosense", "false" ] [ "default_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "minimal_pipe", "inline,remap,deadcode,multiplex,garbageCollector" ] [ "sql_optimizer", "default_pipe" ] [ "sql_debug", "0" ] [ "standoff_ns", "" ] [ "standoff_start", "start" ] [ "standoff_end", "end" ] [ "config", "D:\\Program Files\\MonetDB\\MonetDB5\\etc\\monetdb5.conf" ] [ "mero_pidfile", "D:\\Program Files\\MonetDB\\MonetDB5\\var\\run\\MonetDB\\merovingian.pid" ] [ "mero_controlport", "50001" ] [ "nov2009_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mergetable,deadcode,constants,commonTerms,joinPath,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "replication_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mergetable,deadcode,constants,commonTerms,joinPath,deadcode,reduce,dataflow,history,replication,multiplex,garbageCollector" ] [ "accumulator_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mergetable,deadcode,constants,commonTerms,joinPath,deadcode,reduce,accumulators,dataflow,history,multiplex,garbageCollector" ] [ "recycler_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,deadcode,constants,commonTerms,joinPath,deadcode,recycle,reduce,dataflow,history,multiplex,garbageCollector" ] [ "cracker_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,selcrack,deadcode,constants,commonTerms,joinPath,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "sidcrack_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,sidcrack,deadcode,constants,commonTerms,joinPath,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "datacell_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,deadcode,constants,commonTerms,joinPath,datacell,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "octopus_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,constants,commonTerms,joinPath,octopus,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "mapreduce_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mapreduce,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "datacyclotron_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,datacyclotron,mergetable,deadcode,constants,commonTerms,joinPath,reorder,deadcode,reduce,dataflow,history,replication,multiplex,garbageCollector" ] [ "derive_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mergetable,deadcode,constants,commonTerms,derivePath,joinPath,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "dictionary_pipe", "inline,remap,dictionary,evaluate,costModel,coercions,emptySet,aliases,mergetable,deadcode,constants,commonTerms,joinPath,deadcode,reduce,dataflow,history,multiplex,garbageCollector" ] [ "compression_pipe", "inline,remap,evaluate,costModel,coercions,emptySet,aliases,mergetable,deadcode,constants,commonTerms,joinPath,deadcode,reduce,dataflow,compression,dataflow,history,multiplex,garbageCollector" ] [ "gdk_mem_pagebits", "16" ] [ "gdk_mem_bigsize", "1048576" ] [ "monet_pid", "984" ] [ "monet_version", "5.22.3" ] RD 1298855541546: inserting prompt TD 1298855541562: write final block: 60 bytes TX 1298855541562: sselect * from risk.td_ind_security_held where id = 1560000; RD 1298855541578: read final block: 1600 bytes RX 1298855541578: &1 1 1 30 1 % risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held # table_name % id, bizdate, painnercode, currency, exchange, seccode, basickind, unrealizedgainchange, unrealizedgain, margingain, interestgain, othergain, yieldrate, accrualinterest, allgain, fullmv, marketvalue, lastfullmv, lastmarketvalue, lastcost, cost, buysum, sellsum, realizedgain, holdingqty, lastholdingqty, mvweight, lastmvweight, fullmvweight, lastfullmvweight # name % int, varchar, varchar, varchar, varchar, varchar, varchar, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal # type % 7, 8, 8, 3, 5, 6, 3, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 14, 14, 14, 14 # length RD 1298855541578: inserting prompt TD 1298855762109: write final block: 60 bytes TX 1298855762109: sselect * from risk.td_ind_security_held where id = 1560000; RD 1298855762125: read final block: 1600 bytes RX 1298855762125: &1 2 1 30 1 % risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held # table_name % id, bizdate, painnercode, currency, exchange, seccode, basickind, unrealizedgainchange, unrealizedgain, margingain, interestgain, othergain, yieldrate, accrualinterest, allgain, fullmv, marketvalue, lastfullmv, lastmarketvalue, lastcost, cost, buysum, sellsum, realizedgain, holdingqty, lastholdingqty, mvweight, lastmvweight, fullmvweight, lastfullmvweight # name % int, varchar, varchar, varchar, varchar, varchar, varchar, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal, decimal # type % 7, 8, 8, 3, 5, 6, 3, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 14, 14, 14, 14 # length RD 1298855762125: inserting prompt TD 1298856279453: write final block: 69 bytes TX 1298856279453: sselect id,bizdate from risk.td_ind_security_held where id = 1560000; RD 1298856279453: read final block: 162 bytes RX 1298856279453: &1 3 1 2 1 % risk.td_ind_security_held, risk.td_ind_security_held # table_name % id, bizdate # name % int, varchar # type % 7, 8 # length [ 1560000, "20090702" ] RD 1298856279453: inserting prompt TD 1298856279468: write final block: 1797 bytes TX 1298856279468: sSELECT 'krisk' AS "TABLE_CAT", "schemas"."name" AS "TABLE_SCHEM", "tables"."name" AS "TABLE_NAME", "columns"."name" AS "COLUMN_NAME", cast(CASE "columns"."type" WHEN 'wrd' THEN -5 WHEN 'sec_interval' THEN -5 WHEN 'bigint' THEN -5 WHEN 'timetz' THEN 92 WHEN 'char' THEN 1 WHEN 'int' THEN 4 WHEN 'clob' THEN 2005 WHEN 'month_interval' THEN 4 WHEN 'tinyint' THEN -6 WHEN 'table' THEN 2003 WHEN 'date' THEN 91 WHEN 'double' THEN 8 WHEN 'decimal' THEN 3 WHEN 'timestamptz' THEN 93 WHEN 'timestamp' THEN 93 WHEN 'blob' THEN 2004 WHEN 'real' THEN 7 WHEN 'time' THEN 92 WHEN 'oid' THEN 1111 WHEN 'boolean' THEN 16 WHEN 'smallint' THEN 5 WHEN 'varchar' THEN 12 ELSE 1111 END AS smallint) AS "DATA_TYPE", "columns"."type" AS "TYPE_NAME", "columns"."type_digits" AS "COLUMN_SIZE", "columns"."type_scale" AS "DECIMAL_DIGITS", 0 AS "BUFFER_LENGTH", 10 AS "NUM_PREC_RADIX", cast(CASE "null" WHEN true THEN 1 WHEN false THEN 0 END AS int) AS "NULLABLE", cast(null AS varchar(1)) AS "REMARKS", "columns"."default" AS "COLUMN_DEF", 0 AS "SQL_DATA_TYPE", 0 AS "SQL_DATETIME_SUB", 0 AS "CHAR_OCTET_LENGTH", "columns"."number" + 1 AS "ORDINAL_POSITION", cast(null AS varchar(1)) AS "SCOPE_CATALOG", cast(null AS varchar(1)) AS "SCOPE_SCHEMA", cast(null AS varchar(1)) AS "SCOPE_TABLE", cast(1111 AS smallint) AS "SOURCE_DATA_TYPE", CASE "null" WHEN true THEN CAST ('YES' AS varchar(3)) WHEN false THEN CAST ('NO' AS varchar(3)) END AS "IS_NULLABLE" FROM "sys"."columns" AS "columns", "sys"."tables" AS "tables", "sys"."schemas" AS "schemas" WHERE "columns"."table_id" = "tables"."id" AND "tables"."schema_id" = "schemas"."id" AND LOWER("schemas"."name") LIKE 'risk' AND LOWER("tables"."name") LIKE 'td_ind_security_held' AND LOWER("columns"."name") LIKE 'id' ORDER BY "TABLE_SCHEM", "TABLE_NAME", "ORDINAL_POSITION"; RD 1298856279484: read final block: 853 bytes RX 1298856279484: &1 4 1 22 1 % ., sys.schemas, .tables, .columns, ., .columns, .columns, .columns, ., ., ., ., .columns, ., ., ., ., ., ., ., ., . # table_name % TABLE_CAT, TABLE_SCHEM, TABLE_NAME, COLUMN_NAME, DATA_TYPE, TYPE_NAME, COLUMN_SIZE, DECIMAL_DIGITS, BUFFER_LENGTH, NUM_PREC_RADIX, NULLABLE, REMARKS, COLUMN_DEF, SQL_DATA_TYPE, SQL_DATETIME_SUB, CHAR_OCTET_LENGTH, ORDINAL_POSITION, SCOPE_CATALOG, SCOPE_SCHEMA, SCOPE_TABLE, SOURCE_DATA_TYPE, IS_NULLABLE # name % char, varchar, varchar, varchar, smallint, varchar, int, int, tinyint, tinyint, int, varchar, varchar, tinyint, tinyint, tinyint, int, varchar, varchar, varchar, smallint, varchar # type % 5, 4, 20, 2, 1, 3, 2, 1, 1, 2, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 4, 2 # length [ "krisk", "risk", "td_ind_security_held", "id", 4, "int", 32, 0, 0, 10, 0, NULL, NULL, 0, 0, 0, 1, NULL, NULL, NULL, 1111, "NO" ] RD 1298856279484: inserting prompt TD 1298856279500: write final block: 1802 bytes TX 1298856279500: sSELECT 'krisk' AS "TABLE_CAT", "schemas"."name" AS "TABLE_SCHEM", "tables"."name" AS "TABLE_NAME", "columns"."name" AS "COLUMN_NAME", cast(CASE "columns"."type" WHEN 'wrd' THEN -5 WHEN 'sec_interval' THEN -5 WHEN 'bigint' THEN -5 WHEN 'timetz' THEN 92 WHEN 'char' THEN 1 WHEN 'int' THEN 4 WHEN 'clob' THEN 2005 WHEN 'month_interval' THEN 4 WHEN 'tinyint' THEN -6 WHEN 'table' THEN 2003 WHEN 'date' THEN 91 WHEN 'double' THEN 8 WHEN 'decimal' THEN 3 WHEN 'timestamptz' THEN 93 WHEN 'timestamp' THEN 93 WHEN 'blob' THEN 2004 WHEN 'real' THEN 7 WHEN 'time' THEN 92 WHEN 'oid' THEN 1111 WHEN 'boolean' THEN 16 WHEN 'smallint' THEN 5 WHEN 'varchar' THEN 12 ELSE 1111 END AS smallint) AS "DATA_TYPE", "columns"."type" AS "TYPE_NAME", "columns"."type_digits" AS "COLUMN_SIZE", "columns"."type_scale" AS "DECIMAL_DIGITS", 0 AS "BUFFER_LENGTH", 10 AS "NUM_PREC_RADIX", cast(CASE "null" WHEN true THEN 1 WHEN false THEN 0 END AS int) AS "NULLABLE", cast(null AS varchar(1)) AS "REMARKS", "columns"."default" AS "COLUMN_DEF", 0 AS "SQL_DATA_TYPE", 0 AS "SQL_DATETIME_SUB", 0 AS "CHAR_OCTET_LENGTH", "columns"."number" + 1 AS "ORDINAL_POSITION", cast(null AS varchar(1)) AS "SCOPE_CATALOG", cast(null AS varchar(1)) AS "SCOPE_SCHEMA", cast(null AS varchar(1)) AS "SCOPE_TABLE", cast(1111 AS smallint) AS "SOURCE_DATA_TYPE", CASE "null" WHEN true THEN CAST ('YES' AS varchar(3)) WHEN false THEN CAST ('NO' AS varchar(3)) END AS "IS_NULLABLE" FROM "sys"."columns" AS "columns", "sys"."tables" AS "tables", "sys"."schemas" AS "schemas" WHERE "columns"."table_id" = "tables"."id" AND "tables"."schema_id" = "schemas"."id" AND LOWER("schemas"."name") LIKE 'risk' AND LOWER("tables"."name") LIKE 'td_ind_security_held' AND LOWER("columns"."name") LIKE 'bizdate' ORDER BY "TABLE_SCHEM", "TABLE_NAME", "ORDINAL_POSITION"; RD 1298856279515: read final block: 862 bytes RX 1298856279515: &1 5 1 22 1 % ., sys.schemas, .tables, .columns, ., .columns, .columns, .columns, ., ., ., ., .columns, ., ., ., ., ., ., ., ., . # table_name % TABLE_CAT, TABLE_SCHEM, TABLE_NAME, COLUMN_NAME, DATA_TYPE, TYPE_NAME, COLUMN_SIZE, DECIMAL_DIGITS, BUFFER_LENGTH, NUM_PREC_RADIX, NULLABLE, REMARKS, COLUMN_DEF, SQL_DATA_TYPE, SQL_DATETIME_SUB, CHAR_OCTET_LENGTH, ORDINAL_POSITION, SCOPE_CATALOG, SCOPE_SCHEMA, SCOPE_TABLE, SOURCE_DATA_TYPE, IS_NULLABLE # name % char, varchar, varchar, varchar, smallint, varchar, int, int, tinyint, tinyint, int, varchar, varchar, tinyint, tinyint, tinyint, int, varchar, varchar, varchar, smallint, varchar # type % 5, 4, 20, 7, 2, 7, 1, 1, 1, 2, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 4, 2 # length [ "krisk", "risk", "td_ind_security_held", "bizdate", 12, "varchar", 8, 0, 0, 10, 0, NULL, NULL, 0, 0, 0, 2, NULL, NULL, NULL, 1111, "NO" ] RD 1298856279515: inserting prompt TD 1298856508906: write final block: 77 bytes TX 1298856508906: sselect id,bizdate,allgain from risk.td_ind_security_held where id = 1560000; RD 1298856508906: read final block: 187 bytes RX 1298856508906: &1 6 1 3 1 % risk.td_ind_security_held, risk.td_ind_security_held, risk.td_ind_security_held # table_name % id, bizdate, allgain # name % int, varchar, decimal # type % 7, 8, 20 # length RD 1298856508906: inserting prompt

2 1

[MonetDB-users] wrong results for group by queries
by Daniel Boesswetter 05 May '11

05 May '11

Hi, we are using MonetDB (Oct-2010) for analyzing a 250G data warehouse and have found at least one "thing" which might be a serious bug. The simplest scenario that I have found to describe it, is as follows: SELECT comp.id as compid, comp.name, affnets.name as affid FROM toc INNER JOIN app ON toc.application_id=app.id INNER JOIN comp ON app.company_id = comp.id INNER JOIN affnets ON toc.affiliate_network_id=affnets.id GROUP BY compid, comp.name, affid This query is supposed to return all unique company/affnet pairs which occur in the fact table "toc". However, it returns only the unique company-names, each with a random (the first?) affnet. (Of course, this could be accomplished with DISTINCT, but our aim to to aggregate other fields). If I change the query to select app.company_id as compid, comp.name, affnets.name as affid ... or select comp.id as compid, comp.name, affnets.name as affid ... i.e. semantically the same but only with fields from 2 directly joined tables in the GROUP BY, then the result is correct. Question: Is this a bug or are we missing something? Thank you in advance! Daniel

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[MonetDB-users] Records deleted still appear in: select count(*) from table
by Osmin Castillo 05 May '11

05 May '11

Hi guys: After delete some records from a table using a "delete from table where field=value" criteria, why the "select cont(0) from table" still shows the same records count? Maybe the records are only "marked" and not really removed from the table? Thanks in advance Osmin

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[MonetDB-users] Fwd: wkb representation of a geometry
by Georgios Garmpis 04 May '11

04 May '11

Hi, I need to get the Well Known Binary representation of a geometry but I didn't find any function in documentation to do this. Any ideas? -- George Garbis

4 11

[MonetDB-users] How does MonetDB work
by anjenny 04 May '11

04 May '11

Hey, my name is anjenny and im doin a little research on MonetDB for a project. My Question is How does MonetDB actually work? Greetings anjenny -- View this message in context: http://old.nabble.com/How-does-MonetDB-work-tp31440282p31440282.html Sent from the monetdb-users mailing list archive at Nabble.com.

5 7

[MonetDB-users] Time Interval Overlap
by brien colwell 29 Apr '11

29 Apr '11

Hi all, I have a table that stores a time interval as two timestamps, and want to construct the most efficient query to check whether two intervals in the table overlap. The naive way, using two range conditions [1], seems to choke for large tables. The M5 SQL manual mentions an OVERLAPS operator that, as far as I've read [2], seems to use an optimized interval join algorithm. Can anyone clarify: 1. How to convert a start timestamp and an end timestamp into an interval type 2. How to use the OVERLAPS operator Many thanks. Brien [0] create table intervals as ( id bigint, series_id bigint, start_time timestamp, end_time timestamp ) [1] select a.id as a_id b.id as b_id from intervals a inner join intervals b on b.series_id = a.series_id and b.id < a.id and b.start_time < a.end_time and a.start_time < b.end_time [2] http://monetdb.cwi.nl/XQuery/Documentation/StandOff-Extension.html

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[MonetDB-users] rowcount in monetdb
by Vassilis Papakonstantinou 29 Apr '11

29 Apr '11

Hello all, Is there a way to take the number of rows affected by the last statement just like @@ROWCOUNT in SQL Server or SQL%ROWCOUNT in Oracle? Thanks, Vassilis

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Re: [MonetDB-users] Discontinuation of MonetDB XQuery
by Peter Boncz 29 Apr '11

29 Apr '11

Hi Ryad, There have been plans to port XQuery to MonetDB5, but there has been lack of time and manpower to make this possible. This shortage of resources might change if the database research community regains interest in XQuery in a future. At CWI, a research project, engineering effort must always be justified by ongoing research projects that profit from it. For the moment, it is hard to predict when there will be XML database research projects again, but I would not rule it out. For the moment, you can also just continue to use MonetDB/XQuery. It had not changed much anyway in the past two years, so the change is not dramatic. The software is still available in open source in this April branch of the MonetDB software. So one can still download it in binary, check out the source, change it, compile it and even redistribute it according to the license. CWI for the moment just will not create new releases for it. Peter From: Ryad Ben-El-Kezadri [mailto:ryad.bek@gmail.com] Sent: Friday, April 29, 2011 9:49 AM To: monetdb-users(a)lists.sourceforge.net Subject: [MonetDB-users] Discontinuation of MonetDB XQuery Hello I am a MonetDB XQuery supporter (http://permalink.gmane.org/gmane.comp.db.monetdb.user/3824) and I am sad that it is discontinued. I was very enthusiastic about the software so I was rather excepting an upgrade to MonetDB5. However I am confident that it will be easy to turn my application to MonetDB5. As a basic XQuery user, my questions are threefold: 1)Are there some explanations for this change (flaws in the design of XQuery 2.0, lack of users, performance limitation)? 2)Is MonetDB5 SQL able to store GB of data (as MonetDB XQuery)? Will we observe performance gains for (time ordered) one dimensional data? 3)Is there an equivalent to the XRPC API? Warm regards Ryad

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