[MonetDB-users] Help,how to create hash index on table
Hello,
Current I am using MonetDB server v5.18.3 , and as i see in Wiki , MonetDB support hash index ,I intended to create a hash index on a table. But how to do it , i have referred to sqlmanual downloaded from monetdb.cwi.nl, but it simply wrote following format:
CREATE [UNIQUE] INDEX <index_name> ON <table_name> ( <column_name>, ...) ;
Is that Btree index or hash index or others? Does MonetDB support multiple column hash index? I am looking forward to your reply.
Thanks a lot.
Andrew. Feng
Hello Andrew,
no offense, but could you try to check the mailing list archives before posting questions? The very same question was posted and answered just a few days ago: [1]. And it is rather usual when having a question, that someone else already asked it before
Best regards,
Isidor
[1] http://sourceforge.net/mailarchive/forum.php?thread_name=4BE70EDB.8000602%40...
Hi: Firstly , I am very sorry to send the same message from different Email address before. Probably something wrong in my Outlook Express, it's my fault .
Now I am working on experiment of storing the RDF data in MonetDB ( many researches such as vertically partition , RDF3x, RDFJoin use the MonetDB as database ), and the first step is creating the URI conversion table .( convert the URI into integer serial number ) .
sql> create table soidtable ( url varchar(3000) not null, id int primary key);
and next step is createing POT , PST , SOT table
sql> create table sot ( propertyid1 int ,propertyid2 int, bitvector Blob);
My problem is that I want to create a hash index on URI and later on multiple columns , how can i do it ? this problem has frustrated me for some days. and I have seen that someone asked similar question before in mailing list archives . and someone propose that "do some compilation on your own " [1] . I can't understand what it means.
Any sugguestions and helps will be much appreciated .
Thanks Andrew Feng
[1] http://sourceforge.net/mailarchive/message.php?msg_id=7cc6b5600910052359ta95...
----- Original Message ----- From: "Isidor Zeuner" monetdb@quidecco.de To: monetdb-users@lists.sourceforge.net Sent: Saturday, May 15, 2010 5:21 AM Subject: Re: [MonetDB-users] Help,how to create hash index on table
Hello Andrew,
no offense, but could you try to check the mailing list archives before posting questions? The very same question was posted and answered just a few days ago: [1]. And it is rather usual when having a question, that someone else already asked it before
Best regards,
Isidor
[1] http://sourceforge.net/mailarchive/forum.php?thread_name=4BE70EDB.8000602%40...
MonetDB-users mailing list MonetDB-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-users
Hi,
the compilation refers to the fact that you will have to activate the rdf compilation in the Makefile.ag file of src/modules/mal of the MonetDB5 package and re-compile&re-instal to be able to use the experimental rdf loader.
About the hashes. MonetDB will create hash indices on the fly whenever they are needed. Monet is a self-tuned database and thus requires no input/administration from the user. Even if you issue a CREATE INDEX statement that will be only used at will from monetdb. I would suggest you start experimenting with monetdb and trust that a hash index will be there or created whenever is needed.
lefteris
PS. about the uri conversion table if you are not trying to do updates maybe it is better if you sort it on uri.
On Sat, May 15, 2010 at 9:51 AM, fll 007900800083@sina.com wrote:
Hi: Firstly , I am very sorry to send the same message from different Email address before. Probably something wrong in my Outlook Express, it's my fault .
Now I am working on experiment of storing the RDF data in MonetDB ( many researches such as vertically partition , RDF3x, RDFJoin use the MonetDB as database ), and the first step is creating the URI conversion table .( convert the URI into integer serial number ) .
sql> create table soidtable ( url varchar(3000) not null, id int primary key);
and next step is createing POT , PST , SOT table
sql> create table sot ( propertyid1 int ,propertyid2 int, bitvector Blob);
My problem is that I want to create a hash index on URI and later on multiple columns , how can i do it ? this problem has frustrated me for some days. and I have seen that someone asked similar question before in mailing list archives . and someone propose that "do some compilation on your own " [1] . I can't understand what it means.
Any sugguestions and helps will be much appreciated .
Thanks Andrew Feng
[1] http://sourceforge.net/mailarchive/message.php?msg_id=7cc6b5600910052359ta95...
----- Original Message ----- From: "Isidor Zeuner" monetdb@quidecco.de To: monetdb-users@lists.sourceforge.net Sent: Saturday, May 15, 2010 5:21 AM Subject: Re: [MonetDB-users] Help,how to create hash index on table
Hello Andrew,
no offense, but could you try to check the mailing list archives before posting questions? The very same question was posted and answered just a few days ago: [1]. And it is rather usual when having a question, that someone else already asked it before
Best regards,
Isidor
[1] http://sourceforge.net/mailarchive/forum.php?thread_name=4BE70EDB.8000602%40...
MonetDB-users mailing list MonetDB-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-users
MonetDB-users mailing list MonetDB-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-users
participants (4)
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fll -
Isidor Zeuner -
Lefteris -
冯亮