Archive

Author Archive

Error in rf2 of DBT3 (TPC-H)

February 3rd, 2012

First of all, I am using PostgreSQL. The error message looks like this:

ERROR:  missing FROM-clause entry for table "tmp_orderkey1"
LINE 1: delete from lineitem where l_orderkey=tmp_orderkey1.orderkey...

ERROR:  missing FROM-clause entry for table "tmp_orderkey1"
LINE 1: delete from orders where o_orderkey=tmp_orderkey1.orderkey...

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Coding

A bug in DBT3 (TPC-H)

February 2nd, 2012

First of all, this bug may not occur in every environment. I suspect that it has something to do the implementation of C library on your machine, specifically, the implementation of function “strcpy”.
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Coding

Write a kernel module that its parameters can be dynamically changed

February 2nd, 2012

We know that every Linux kernel module can accept parameters from command line when it is first loaded, but sometimes we want to change the behavior of a module on the fly, without requiring the module to be removed and inserted again. To achieve this flexibility, we take advantage of the sysfs.
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Coding

Location of the kernel symbol table on Fedora Linux

February 2nd, 2012

check out /proc/kallsyms. You don’t have to be a root to read its content. The normal place “/proc/ksyms” does not exist on my Fedora.
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Coding

Some notes about compiling DBT3 (TPC-H)

February 1st, 2012

As described in the INSTALL file, first run
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Database

DBT3 (TPC-H) user manual

February 1st, 2012

I just want to post it here, so I don’t need to compile from source every time:
dbt3-user (pdf)

Database

Control flow of a query in PostgreSQL

January 27th, 2012

As of version 9.0.4
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Database

Adjust Vim split window size

January 18th, 2012

1. Change the height (number of rows) of a split window
To increase by 10, type command

:res+10

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Coding

A TPC-H Q21 query plan

November 27th, 2011

Configuration:
PostgreSQL 9.0.4. memsize/data size = 1/8
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Database

Tables and Indexes created by DBT2

August 25th, 2011

For those who didn’t know, DBT2 is an implementation of TPCC benchmark. Following is a list of tables and indexes created:
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Database