- users-list - monetdb.org

Positional placeholders in prepared statement
by Frank Tetzel 29 Jun '16

29 Jun '16

Hi, does MonetDB support positional placeholders like '$1' instead of just '?' in prepared statements? I want to refer to a parameter more than once and possibly also out of order. Is there some alternative available? Regards, Frank

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Resetting monetdb administrative password
by Roman S 29 Jun '16

29 Jun '16

Hello, Can somebody tell me how to reset monetdb administrative password? I’ve tried to stop mserver5, start it manually, oldp:=clients.getPasswordHash(“monetdb"); newp:=clients.backendsum("newpassword"); clients.changePassword(oldp, newp); Stoping it again and start in normal mode But it didn’t help: mclient --database=mydb --user=monetdb password:<usingnewpass> InvalidCredentialsException:checkCredentials:invalid credentials for user 'monetdb'

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MERGE Tables works ?
by Ariel Abadi 28 Jun '16

28 Jun '16

Hi Everybody! Im facing a problem. We register telecomunications calls. As the volume is so big, we decided to store the data in different tables. The criteria we used for splitting the info was to create a table per each Switch and Day. So we have Sw1_20160601, Sw2_20160602...Sw3_20160620..etc etc Each table has aprox 15MM rows. In order to create some reports we have created a *MERGE TABLE *and added to this table the 90 tables (3 switches x 30 days). BUT, now Im trying to run a very simple query, like SELECT cdr_date FROM xxxx LIMIT 3; To get at least 3 rows (just to see that this schema works). It took 21 mins to give me those 3 rows.... Am I doing something wrong? Rgds Ariel

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Announcement: New Jun2016 Feature release of MonetDB suite
by Sjoerd Mullender 23 Jun '16

23 Jun '16

The MonetDB team at CWI/MonetDB BV is pleased to announce the Jun2016 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/>. Jun 2016 feature release MonetDB5 Server * Extended the storage() table producing function to also accept storage([schemaname [, tablename [, columnname]]]) * The :bat[:oid,:any] type descriptor has been turned into its columnar version :bat[:any] * Converted the *.mal scripts into *.malC versions to prepare for removal of the mserver console. * Removed functions mat.hasMoreElements, mat.info, mat.mergepack, mat. newIterator, mat.project, mat.pack2, mat.sortReverse, mat.sort, and mat.slice. * Removed grouped aggregate functions from the aggr module in which the groups were indicated by the head column of the bat to be aggregated. Use the interface with a separate group bat instead. * The server now stops executing a query when the client disconnects. * Removed algebra.join. Use algebra.subjoin instead. * Removed algebra.antijoin. Use algebra.subantijoin or algebra.subthetajoin instead. * The MAL function 'leftfetchjoin' is renamed to its relational algebra version 'projection' * The generic property handling scheme has been removed. It was used in just a few places, for widely different purposes and contained cruft. * Removed functions str.iconv and str.codeset. Internally, strings are always in UTF-8 encoding, so we can't allow code set conversions. * Removed algebra.like with a BAT argument. Use algebra.likesubselect instead. * Removed algebra.leftjoin. Use algebra.subleftjoin or algebra.leftfetchjoin instead. * Removed algebra.tdiff and algebra.tinter. * Removed algebra.sample. Use sample.subuniform instead. * Removed algebra.select. Use algebra.subselect instead. * Removed algebra.revert. * Removed bat.order and bat.orderReverse functions. * Changed client.getUsers to return two bats, one with the user id and one with the user name. * Implemented algebra.subdiff and algebra.subinter. * Removed algebra.tdifference and algebra.tintersect. * Removed algebra.tunion. Build Environment * A new package MonetDB-lidar (Fedora) or libmonetdb5-server-lidar (Debian/Ubuntu) has been created to work with LiDAR data. * Implemented a systemd configuration file for a monetdbd.service on systems that support it (Fedora, newer Ubuntu). Client Package * The Ruby client is now in a separate repository (http://dev.monetdb.org/hg/monetdb-ruby) and released independently. Geom Module * The geom module has been completely overhauled. Types are now specified as GEOMETRY(POINT) instead of POINT, old functions have been removed, new ones introduced. However, even with all the changes, a database upgrade should still be possible (as always, make a backup first). MonetDB Common * Removed BATconst. Use BATconstant instead. * Changed BATconstant. It now has a new first argument with the seqbase for the head column. * Removed BATmmap. It was no longer used. * BUNdelete and BATdel don't accept a foce argument and only allow deleting values that have not yet been committed. BUNdelete exchanges the deleted value with the last value (if the deleted value isn't the last value). BATdel compacts the BAT by shifting values after the deleted values up. The list of to-be-deleted values in BATdel must be sorted and unique. * Removed BUNreplace from list of exported functions. It wasn't used, and there is still BUNinplace and void_inplace that do more-or-less the same thing. * Changed BATderiveHeadProps to BATderiveTailProps (and it now works on the tail column). * Removed unused functions BATalpha, BATdelta, and BATprev. * Removed function VIEWcombine. Use BATdense instead. * Removed "left" parameter from BUNinplace. It wasn't used since the BAT it works on is dense headed. * Created function BATdense to easily create a [void,void] BAT with specified seqbases for head and tail and a count. * Removed function BATmark. When all head columns are dense, BATmark basically only created a new [void,void] BAT. * Renamed BATsubsort to BATsort. * Removed "sub" from the names of the function BATsubselect, BATthetasubselect, BATsubcross, BATsubleftjoin, BATsubouterjoin, BATsubthetajoin, BATsubsemijoin, BATsubdiff, BATsubjoin, BATsubbandjoin, BATsubrangejoin, and BATsubunique. * Removed BATsubleftfetchjoin: it was not used. * Removed BATcross1. Use BATsubcross instead. * Removed all versions of the SORTloop macro. * Removed Batkdiff. Use BATsubdiff instead. * Removed BATselect. Use BATsubselect instead. * Removed BATsemijoin. Use BATsubsemijoin instead. * Removed BATjoin. Use BATsubjoin instead. * Removed BATleftjoin. Use BATsubleftjoin or BATproject instead. * Removed BATleftfetchjoin. Use BATproject instead. * Removed BUNins from the list of exported functions. * Removed legacy functions BATuselect and BATuselect_. * Removed legacy functions BATantijoin, BATbandjoin, BATouterjoin, BATrangejoin, and BATthetajoin. * Removed function BATrevert. * BATordered now works on the TAIL column. * Removed obsolete functions BATorder() and BATorder_rev(). * Implemented BATsubdiff which returns a list of OIDs (sorted, i.e. usable as candidate list) of tuples in the left input whose value does not occur in the right input. * Removed function BATkintersect. It wasn't used anymore. It's functionality can be obtained by using BATsubsemijoin. * Removed the function BATkunion. Java Module * Fixed problem in DatabaseMetaData.getUDTs() when it was called with types parameter filled. It used to throw SQException with message: SELECT: identifier 'DATA_TYPE' unknown. Now it returns the UDTs which match the provided array of data types. * Implemented MonetDatabaseMetaData.supportsConvert() and MonetDatabaseMetaData.supportsConvert(int fromType, int toType) methods. It used to always return false. Now it returns true for the supported conversions. This fixes Bug 3460. * ResultSet.setFetchSize(): added a dummy implementation to get rid of the SQLFeatureNotSupportedException. In MonetDB, it does not make sense to set the fetch size of a result set. If one really wants to set the fetch size, one should use Statement.setFetchSize() instead. * Fixed resource leak in ResultSetMetaData. It created and cached a ResultSet object for each column but never closed the ResultSet objects. * Corrected DatabaseMetaData methods which accept a catalog filter argument. Those methods will now filter the results on the specified catalog name, whereas previously the catalog filter argument was ignored. * Corrected output of column KEY_SEQ of DatabaseMetaData methods: getPrimaryKeys(), getImportedKeys(), getExportedKeys() and getCrossReference(). It now starts at 1 instead of 0 previously. * Corrected DatabaseMetaData.getSchemas() by returning 2 instead of 3 columns. * Improved DatabaseMetaData.getColumns() by returning two additional columns: IS_AUTOINCREMENT and IS_GENERATEDCOLUMN. * Improved DatabaseMetaData.getTypeInfo(). It now returns better information on LITERAL_PREFIX, LITERAL_SUFFIX, CREATE_PARAMS, CASE_SENSITIVE, FIXED_PREC_SCALE and MAXIMUM_SCALE for some data types. Also the returned rows are now ordered by DATA_TYPE, TYPE_NAME, PRECISION as required by the specs. Also corrected output column names "searchable" into "SEARCHABLE" and "MAXIMUM SCALE" into "MAXIMUM_SCALE" to match the JDBC specification. * Corrected DatabaseMetaData.getPseudoColumns(). It used to return 12 empty rows. Now it returns no rows as MonetDB does not have pseudo columns. * Implemented method DatabaseMetaData.getClientProperties(). It used to always return a resultset with 4 completely empty rows. It now returns a resultset with the possible connection properties. * Implemented method DatabaseMetaData.getUDTs(). It used to return an empty resultset. Now it returns the User Defined Types such as inet, json, url and uuid. * Corrected the returned table types in DatabaseMetaData.getTableTypes(). It now returns all 10 table types (as stored in sys.table_types) instead of the previously 8 hardcoded table types. For old MonetDB servers which do not have the sys.table_types table, the old behavior is retained. * Implemented methods DatabaseMetadata.getProcedures() and DatabaseMetadata.getProcedureColumns(). They used to return an empty resultset. Now they return the expected Procedures and ProcedureColumns. Also getProcedureColumns() now returns a resultset with all 20 columns instead of 13 columns previously. * Method getFunctionColumns() in DatabaseMetadata used to throw an SQLException: getFunctionColumns(String, String, String, String) is not implemented. This method is now implemented and returns a resultset. * Method getFunctions() in DatabaseMetadata used to throw an SQLException: SELECT: no such column 'functions.sql' This has been corrected. It now returns a resultset as requested. * The resultsets of DatabaseMetadata methods now no longer return a value for the *_CAT columns as MonetDB does not support Catalogs. * Fixed a memory leak in MonetDatabaseMetaData.java for a static cache which kept references to closed Connection objects. * Improved JdbcClient program when presenting query data to console. It used to send an SQL catalog query for each query result column which slowed down the interactive response considerably. These additional SQL catalog queries have been eliminated. * Corrected MonetResultSet.getObject(String columnName). It no longer throws a NullPointerException in cases where internally a MonetVirtualResultSet is used. * Fixed Connection.isValid(): this method should never attempt to close the connection, even if an error has occurred. SQL * Disallow GRANT <some-user> TO <role-or-use>. Only explicitly created roles can be granted. * Extended grantable schema privileges: when a user is granted the "sysadmin" role, the user now hcan not only create schemas, but also drop schemas. * Introduced COPY INTO/ COPY FROM global privileges. These privileges allows other users than 'monetdb' to be granted the privileges to use the MonetDB bulk data loading/exporting features, i.e., COPY FROM <file> and COPY INTO <file>. Bug Fixes * 2407: Merovingian: allow binds to given ip/interface * 2815: No SRID support * 3361: constants as MAL function parameters prevent intermediate reuse * 3374: UNIQUE constraint does not set tkey property on the corresponding BAT * 3460: incomplete implementation of JDBC driver supportsConvert(), supportsConvert(int fromType, int toType) methods in MonetDatabaseMetaData.java * 3711: JDBC connection using jdbcclient.jar is very slow * 3877: MonetDBLite should allow close then re-open databases? without restarting R * 3911: Invalid connect() call in 'redirect' mode * 3920: query with DISTINCT and correlated scalar subquery in SELECT list causes Assertion failure and crash of mserver5 * 3927: COUNT( distinct my_clob ) , QUANTILE( my_double , number ) fails in dev build * 3956: MonetDBLite unable to execute LIMIT 1 statement * 3972: Drastic Memory leak of 600GBs while generating plan for Query with 25 joins * 3974: Prepared statement rel_bin.c:2378: rel2bin_project: Assertion `0' failed. * 3975: Suspicious code in store_manager() on exit path * 3978: SQL returns TypeException 'aggr.subcorr' undefined for sys.corr function * 3980: JOIN with references on both sides crashes mserver * 3981: Incorrect LEFT JOIN when FROM clause contains nested subqueries * 3983: Creation of a Foreign Key which partially maps to a primary key is accepted without a warning * 3984: Multiple paths in the .profile * 3985: ruby-monetdb-sql gem fails for negative timezone offset (USA, etc.) * 3987: Segfault on malformed csv import * 3991: MonetDBLite feature request: default monetdb.sequential to FALSE on windows * 3994: MonetDBLite dbDisconnect with shutdown=TRUE freezes the console on windows * 3995: NullPointerException when calling getObject() * 3997: calling scalar functions sys.isaUUID(str) or sys.isaUUID(uuid) fail * 3999: length() returns wrong length for strings which have spaces at the end of the string * 4010: RELEASE SAVEPOINT after ALTER TABLE crashes mserver5 * 4011: sys.sessions.user column always shows 'monetdb' * 4013: GDKextendf does not free up memory when it fails due to insufficient resources * 4015: Daemon crashes on database release command

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Announcement: New Jun2016 Feature release of MonetDB suite
by Sjoerd Mullender 23 Jun '16

23 Jun '16

The MonetDB team at CWI/MonetDB BV is pleased to announce the Jun2016 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/>. Jun 2016 feature release MonetDB5 Server * Extended the storage() table producing function to also accept storage([schemaname [, tablename [, columnname]]]) * The :bat[:oid,:any] type descriptor has been turned into its columnar version :bat[:any] * Converted the *.mal scripts into *.malC versions to prepare for removal of the mserver console. * Removed functions mat.hasMoreElements, mat.info, mat.mergepack, mat. newIterator, mat.project, mat.pack2, mat.sortReverse, mat.sort, and mat.slice. * Removed grouped aggregate functions from the aggr module in which the groups were indicated by the head column of the bat to be aggregated. Use the interface with a separate group bat instead. * The server now stops executing a query when the client disconnects. * Removed algebra.join. Use algebra.subjoin instead. * Removed algebra.antijoin. Use algebra.subantijoin or algebra.subthetajoin instead. * The MAL function 'leftfetchjoin' is renamed to its relational algebra version 'projection' * The generic property handling scheme has been removed. It was used in just a few places, for widely different purposes and contained cruft. * Removed functions str.iconv and str.codeset. Internally, strings are always in UTF-8 encoding, so we can't allow code set conversions. * Removed algebra.like with a BAT argument. Use algebra.likesubselect instead. * Removed algebra.leftjoin. Use algebra.subleftjoin or algebra.leftfetchjoin instead. * Removed algebra.tdiff and algebra.tinter. * Removed algebra.sample. Use sample.subuniform instead. * Removed algebra.select. Use algebra.subselect instead. * Removed algebra.revert. * Removed bat.order and bat.orderReverse functions. * Changed client.getUsers to return two bats, one with the user id and one with the user name. * Implemented algebra.subdiff and algebra.subinter. * Removed algebra.tdifference and algebra.tintersect. * Removed algebra.tunion. Build Environment * A new package MonetDB-lidar (Fedora) or libmonetdb5-server-lidar (Debian/Ubuntu) has been created to work with LiDAR data. * Implemented a systemd configuration file for a monetdbd.service on systems that support it (Fedora, newer Ubuntu). Client Package * The Ruby client is now in a separate repository (http://dev.monetdb.org/hg/monetdb-ruby) and released independently. Geom Module * The geom module has been completely overhauled. Types are now specified as GEOMETRY(POINT) instead of POINT, old functions have been removed, new ones introduced. However, even with all the changes, a database upgrade should still be possible (as always, make a backup first). MonetDB Common * Removed BATconst. Use BATconstant instead. * Changed BATconstant. It now has a new first argument with the seqbase for the head column. * Removed BATmmap. It was no longer used. * BUNdelete and BATdel don't accept a foce argument and only allow deleting values that have not yet been committed. BUNdelete exchanges the deleted value with the last value (if the deleted value isn't the last value). BATdel compacts the BAT by shifting values after the deleted values up. The list of to-be-deleted values in BATdel must be sorted and unique. * Removed BUNreplace from list of exported functions. It wasn't used, and there is still BUNinplace and void_inplace that do more-or-less the same thing. * Changed BATderiveHeadProps to BATderiveTailProps (and it now works on the tail column). * Removed unused functions BATalpha, BATdelta, and BATprev. * Removed function VIEWcombine. Use BATdense instead. * Removed "left" parameter from BUNinplace. It wasn't used since the BAT it works on is dense headed. * Created function BATdense to easily create a [void,void] BAT with specified seqbases for head and tail and a count. * Removed function BATmark. When all head columns are dense, BATmark basically only created a new [void,void] BAT. * Renamed BATsubsort to BATsort. * Removed "sub" from the names of the function BATsubselect, BATthetasubselect, BATsubcross, BATsubleftjoin, BATsubouterjoin, BATsubthetajoin, BATsubsemijoin, BATsubdiff, BATsubjoin, BATsubbandjoin, BATsubrangejoin, and BATsubunique. * Removed BATsubleftfetchjoin: it was not used. * Removed BATcross1. Use BATsubcross instead. * Removed all versions of the SORTloop macro. * Removed Batkdiff. Use BATsubdiff instead. * Removed BATselect. Use BATsubselect instead. * Removed BATsemijoin. Use BATsubsemijoin instead. * Removed BATjoin. Use BATsubjoin instead. * Removed BATleftjoin. Use BATsubleftjoin or BATproject instead. * Removed BATleftfetchjoin. Use BATproject instead. * Removed BUNins from the list of exported functions. * Removed legacy functions BATuselect and BATuselect_. * Removed legacy functions BATantijoin, BATbandjoin, BATouterjoin, BATrangejoin, and BATthetajoin. * Removed function BATrevert. * BATordered now works on the TAIL column. * Removed obsolete functions BATorder() and BATorder_rev(). * Implemented BATsubdiff which returns a list of OIDs (sorted, i.e. usable as candidate list) of tuples in the left input whose value does not occur in the right input. * Removed function BATkintersect. It wasn't used anymore. It's functionality can be obtained by using BATsubsemijoin. * Removed the function BATkunion. Java Module * Fixed problem in DatabaseMetaData.getUDTs() when it was called with types parameter filled. It used to throw SQException with message: SELECT: identifier 'DATA_TYPE' unknown. Now it returns the UDTs which match the provided array of data types. * Implemented MonetDatabaseMetaData.supportsConvert() and MonetDatabaseMetaData.supportsConvert(int fromType, int toType) methods. It used to always return false. Now it returns true for the supported conversions. This fixes Bug 3460. * ResultSet.setFetchSize(): added a dummy implementation to get rid of the SQLFeatureNotSupportedException. In MonetDB, it does not make sense to set the fetch size of a result set. If one really wants to set the fetch size, one should use Statement.setFetchSize() instead. * Fixed resource leak in ResultSetMetaData. It created and cached a ResultSet object for each column but never closed the ResultSet objects. * Corrected DatabaseMetaData methods which accept a catalog filter argument. Those methods will now filter the results on the specified catalog name, whereas previously the catalog filter argument was ignored. * Corrected output of column KEY_SEQ of DatabaseMetaData methods: getPrimaryKeys(), getImportedKeys(), getExportedKeys() and getCrossReference(). It now starts at 1 instead of 0 previously. * Corrected DatabaseMetaData.getSchemas() by returning 2 instead of 3 columns. * Improved DatabaseMetaData.getColumns() by returning two additional columns: IS_AUTOINCREMENT and IS_GENERATEDCOLUMN. * Improved DatabaseMetaData.getTypeInfo(). It now returns better information on LITERAL_PREFIX, LITERAL_SUFFIX, CREATE_PARAMS, CASE_SENSITIVE, FIXED_PREC_SCALE and MAXIMUM_SCALE for some data types. Also the returned rows are now ordered by DATA_TYPE, TYPE_NAME, PRECISION as required by the specs. Also corrected output column names "searchable" into "SEARCHABLE" and "MAXIMUM SCALE" into "MAXIMUM_SCALE" to match the JDBC specification. * Corrected DatabaseMetaData.getPseudoColumns(). It used to return 12 empty rows. Now it returns no rows as MonetDB does not have pseudo columns. * Implemented method DatabaseMetaData.getClientProperties(). It used to always return a resultset with 4 completely empty rows. It now returns a resultset with the possible connection properties. * Implemented method DatabaseMetaData.getUDTs(). It used to return an empty resultset. Now it returns the User Defined Types such as inet, json, url and uuid. * Corrected the returned table types in DatabaseMetaData.getTableTypes(). It now returns all 10 table types (as stored in sys.table_types) instead of the previously 8 hardcoded table types. For old MonetDB servers which do not have the sys.table_types table, the old behavior is retained. * Implemented methods DatabaseMetadata.getProcedures() and DatabaseMetadata.getProcedureColumns(). They used to return an empty resultset. Now they return the expected Procedures and ProcedureColumns. Also getProcedureColumns() now returns a resultset with all 20 columns instead of 13 columns previously. * Method getFunctionColumns() in DatabaseMetadata used to throw an SQLException: getFunctionColumns(String, String, String, String) is not implemented. This method is now implemented and returns a resultset. * Method getFunctions() in DatabaseMetadata used to throw an SQLException: SELECT: no such column 'functions.sql' This has been corrected. It now returns a resultset as requested. * The resultsets of DatabaseMetadata methods now no longer return a value for the *_CAT columns as MonetDB does not support Catalogs. * Fixed a memory leak in MonetDatabaseMetaData.java for a static cache which kept references to closed Connection objects. * Improved JdbcClient program when presenting query data to console. It used to send an SQL catalog query for each query result column which slowed down the interactive response considerably. These additional SQL catalog queries have been eliminated. * Corrected MonetResultSet.getObject(String columnName). It no longer throws a NullPointerException in cases where internally a MonetVirtualResultSet is used. * Fixed Connection.isValid(): this method should never attempt to close the connection, even if an error has occurred. SQL * Disallow GRANT <some-user> TO <role-or-use>. Only explicitly created roles can be granted. * Extended grantable schema privileges: when a user is granted the "sysadmin" role, the user now hcan not only create schemas, but also drop schemas. * Introduced COPY INTO/ COPY FROM global privileges. These privileges allows other users than 'monetdb' to be granted the privileges to use the MonetDB bulk data loading/exporting features, i.e., COPY FROM <file> and COPY INTO <file>. Bug Fixes * 2407: Merovingian: allow binds to given ip/interface * 2815: No SRID support * 3361: constants as MAL function parameters prevent intermediate reuse * 3374: UNIQUE constraint does not set tkey property on the corresponding BAT * 3460: incomplete implementation of JDBC driver supportsConvert(), supportsConvert(int fromType, int toType) methods in MonetDatabaseMetaData.java * 3711: JDBC connection using jdbcclient.jar is very slow * 3877: MonetDBLite should allow close then re-open databases? without restarting R * 3911: Invalid connect() call in 'redirect' mode * 3920: query with DISTINCT and correlated scalar subquery in SELECT list causes Assertion failure and crash of mserver5 * 3927: COUNT( distinct my_clob ) , QUANTILE( my_double , number ) fails in dev build * 3956: MonetDBLite unable to execute LIMIT 1 statement * 3972: Drastic Memory leak of 600GBs while generating plan for Query with 25 joins * 3974: Prepared statement rel_bin.c:2378: rel2bin_project: Assertion `0' failed. * 3975: Suspicious code in store_manager() on exit path * 3978: SQL returns TypeException 'aggr.subcorr' undefined for sys.corr function * 3980: JOIN with references on both sides crashes mserver * 3981: Incorrect LEFT JOIN when FROM clause contains nested subqueries * 3983: Creation of a Foreign Key which partially maps to a primary key is accepted without a warning * 3984: Multiple paths in the .profile * 3985: ruby-monetdb-sql gem fails for negative timezone offset (USA, etc.) * 3987: Segfault on malformed csv import * 3991: MonetDBLite feature request: default monetdb.sequential to FALSE on windows * 3994: MonetDBLite dbDisconnect with shutdown=TRUE freezes the console on windows * 3995: NullPointerException when calling getObject() * 3997: calling scalar functions sys.isaUUID(str) or sys.isaUUID(uuid) fail * 3999: length() returns wrong length for strings which have spaces at the end of the string * 4010: RELEASE SAVEPOINT after ALTER TABLE crashes mserver5 * 4011: sys.sessions.user column always shows 'monetdb' * 4013: GDKextendf does not free up memory when it fails due to insufficient resources * 4015: Daemon crashes on database release command

1 0

MonetDB vs. the new MariaDB ColumnStore
by Arno Mittelbach 20 Jun '16

20 Jun '16

Hi all, MariaDB has released a first alpha version of their new ColumnStore (which is essentially InfiniDB). We have done a first tentative performance test and did a comparison of MariaDB ColumnStore vs. MonetDB. For most of the test cases, MonetDB wins hands down. If you are interested in the numbers, have a look at https://reportserver.net/blog/2016/06/20/mariadb-columnstore-vs-innodb-vs-m… Best Regards, Arno

1 0

NULL value with embedded py
by Stefano Fioravanzo 20 Jun '16

20 Jun '16

Hello, I am creating a table using the result of an embedded py function. The result of the function is a dictionary composed of numpy arrays. The function and the CREATE TABLE work well. Inside the arrays of the dictionary, I have a few np.nan values, they seem to be recognized by monet during the creation of the table. In fact, when I query the whole table, I can see ‘null’ in the proper places. But if I try to compare against these null values, I get nothing (SELECT * FROM table where field is null). After a few trials, it seems to me that monet understands that np.nan is a NULL value, but then when it inserts the value into the table the internal representation (?) is somewhat different form a ‘normal’ NULL value. Any suggestion? Thanks, Stefano

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Recover an inconsistent database?
by Vijay Krishna 20 Jun '16

20 Jun '16

Hi, I'm getting the following error while starting a database. *!FATAL: Logger_new: inconsistent database, catalog does not exist* Is there any means to recover this database with data and start it? Or, the only way is to create a new database? (P.S.: There is no backup of data) Thanks & Regards, Vijay.

1 0

aggregation with complex function
by Stefano Fioravanzo 16 Jun '16

16 Jun '16

Hello, I have an embedded python function which, given two integer parameters, after doing some stuff returns a table. I would like to group by a table by these two input parameter, and for each resulting group call the function. The result would be the concatenation of all the tables returned by the function. I understand that a thing like this would be very easy if the function returned just one value e.g.: select my_aggr_function(value1, value2) from table group by value1, value2 But how can I do this if my_aggr_function returns multiple rows?? Thank you, Stefano

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Dynamic Queries
by Ariel Abadi 16 Jun '16

16 Jun '16

Hi Im trying to create a Procedure to create (or not) tables dynamically. Does Monet can do something like the following?? CREATE PROCEDURE(pdate date, tname varchar(10)) BEGIN SET TABLENAME = CONCAT(tname, '_', YEAR(pdate)*100+MONTH(pdate)); CREATE TABLE IF NOT EXIST TABLENAME; END Thanks in advance! Rgds

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