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How to not export data in Ispirer SQLWays

Ispirer SQLWays is a nice (although commercial) tool to convert DDL and data from one supported database to another. We are using it regularly, the list of supported databases is impressive: PostgreSQL, Greenplum, Oracle, SQL Server, IBM DB2, MySQL, Sybase, Informix, Teradata, *Netezza *and some more.

There’s just one thing which I always forget: SQLways exports all data by default, which makes the export unnecessary big and slow.


Wikipedia im Löschwahn

Die deutsche Wikipedia hat es wieder mal geschafft: einige bekannte Open Source Veranstaltungen wurden wegen Irrelevanz gelöscht.


Bericht: PostgreSQL auf der FrOSCon 2010

Die FrOSCon 2010 ist bereits ein paar Tage vorüber, Zeit für einen Bericht.

Es waren nicht ganz so viele Besucher vor Ort wie im letzten Jahr, das ist aber wohl dem sehr warmen Wetter geschuldet. Die Veranstalter haben ausgebaut und noch mehr Projekte untergebracht. Für das nächste Jahr wünsche ich mir allerdings etwas mehr Platz vor den einzelnen Projekttischen - wenn vor zwei gegenüberliegenden Tischen jeweils ein Besucher stand, war schon kein Platz mehr, um dazwischen durchzugehen. Alles in allem war es aber wieder eine gelungene Open-Source Veranstaltung.


Rename a database in MySQL

Ever tried to rename a database in MySQL? Obviously not.

Why not? MySQL does not support renaming databases. Funny, eh?


MySQL: what shall be repaired?

A website shows the following error message:

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SQLSTATE[HY000]: General error: 126 Incorrect key file for table '/tmp/#sql_1898_0.MYI'; try to repair it

So, MySQL: which table is to repair? The error message is not a table, it’s just the temp file.

Stupid and useless error message …


About this new MySQL Emulation Layer in PostgreSQL 9.0

This blog post of mine about the new MySQL Emulation Layer in PostgreSQL 9.0 was (more of less obvious) an April joke. Most readers have guessed it right.

On the other hand: the idea, that this joke is based on, is very real: during the last conferences and exhibitions which I have attended, many visitors asked us (the PostgreSQL booth staff) about the future of MySQL.

Guess what - we don’t know! Please ask Larry ;-)


PostgreSQL 9.0: Includes the new MySQL Emulation Layer

PostgreSQL 9.0.0, released today, contains the MySQL Emulation Layer.

To enable this feature, set the mysql_compatible option GUC to on.


PostgreSQL @ CeBIT 2010

The PostgreSQL User Group Germany were given the opportunity to have a booth at CeBIT 2010 and present the project. CeBIT is a very big IT-related exhibition and takes place in Hannover, Germany.


Support your database!

Happened on IRC, just minutes ago:

22:35:09 -!- michi7x7 has joined #postgresql
22:35:14 < michi7x7> hi all
22:35:44 < michi7x7> i have a problem with a mysql-query, but #mysql is full of mysql-lover-noobs

Users start asking the PostgreSQL-folks for MySQL-support. Times are changing ;-)


MySQL: SQLSTATE[HY000]: General error: 3 Error writing file '/tmp/xyz' (Errcode: 28)

If you run MySQL and this error occurs:

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 SQLSTATE[HY000]: General error: 3 Error writing file '/tmp/MYh0VgDS' (Errcode: 28)

then check if your server isn’t using the famous “overflow” filesystem for /tmp, limited to 1 MB space.

The MySQL error message is - as usual - misleading and non-descriptive.

There are many other possible causes for this error code, so this one here might just be a hint.