Data, data en nog eens data

Category: nice to know

  • Ranking the rows

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    tom
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    I was asked a few days to write a SQL that would retrieve the one but latest row. Take as an example a few rows below: we have a several functions with their min salary. The question is: which function earns the one but highest minumum salary. In the rows below, we have minimum salary…

  • SQLite

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    tom
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    SQLite is the smallest database server we know. The engine itsself is about 500 KB – considerably less than other engines. It can be downloaded from http://www.sqlite.org/ . Once downloaded, it can be started by: sqlite3 test.db. Here, the sqlite3 is the database engine that is called and test.db the database. I have downloaded a…

  • Creating a cookie

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    tom
    in

    Cookies are small items that can be written on the hard disk of a client computer. In Google Chrome, these cookies can be found in a binary file. I found this file in “C:\Users\tmaanen.CORP\AppData\Local\Google\Chrome\User Data\Default\Cookies”. These files can be written on request of the webserver. I wrote a small PHP programme that writes these cookies…

  • OLE DB

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    tom
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    Today, I tried to link a ODBC compliant database to a SAS programme. SAS is a programme, much like Perl, that allows data to be read, transformed and written back to a database. SAS claims that it is able to use OLE DB to hook up to ODBC compliant databases. The idea is that the…

  • The tragedy of not usings dates

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    tom
    in

    I now work with a financial institute where they took the decision NOT to use date formats for data-values. This meant that they use 20110310 to indicate the 10th March 2011. It was possible to use a date format but it was decided to use a numerical format. Everything goes at a cost. Likewise, misusing a…

  • Run ODBC

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    tom
    in

    In some environments, the possibility to create an ODBC link is prohibited. Due to misunderstood security issues, the creation of an ODBC link is not permitted. But is might be that we have a way out! Try C:\Windows\SysWOW64\odbcad32.exe to use the 32 bits version and the 64 bit ODBC drivers via: C:\Windows\System32\odbcad32.exe And there is…

  • send mail via telnet

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    tom
    in

    I am subscribed to a ADSL provider who also provides Email services. Hence, I could try to send some mail from the command line on my laptop. As a first step, I started a telnet session with the provider: from the command line I gave the command: “telnet mail.wxs.nl 25”. The server responded promptly. As response…

  • Google Refine

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    tom
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    I am subscribed to several blogs. One such blog is a blog from Dylan Jones that is maintained from the “Data Quality Pro community”. From this blog I got the suggestion to investigate Google Refine. And it was surely a worthwhile investment. Google Refine is a tool that is acquired by Google to improve data…

  • Moving to Joomla

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    tom
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    Previous pages can be found here I had a site previously. This was basically a standard HTML based site to which comments were added over time. Above link brings you back to these pages. But only a few days ago, I discovered Joomla. This Joomla is a template that allows you to add comments and…

  • NAS Server

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    tom
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    Recently I bought a NAS server. Just to store some files, photos and one or two movies that came across. To be honest, I did not realise how much software was added to this NAS. When I opened the admin page, I was almost shocked with the tons of software that came across: MySQL, PHP,…