Posted by jpluimers on 2017/08/02
I thought I posted a reference to this a long time ago, but didn’t.
It’s one of the things I show when explaining joins to people. Sometimes I need it myself too (:
The article explains these in greater detail:
- INNER JOIN
- LEFT JOIN
- RIGHT JOIN
- OUTER JOIN
- LEFT JOIN EXCLUDING INNER JOIN
- RIGHT JOIN EXCLUDING INNER JOIN
- OUTER JOIN EXCLUDING INNER JOIN
Note:
- the opposite of INNER JOIN is not OUTER JOIN. It’s OUTERJOIN EXCLUDING INNER JOIN
- the opposite of OUTER JOIN is empty set.
But the diagram is usually speaks for itself.
–jeroen
Source: Visual Representation of SQL Joins – CodeProject
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Posted in Access, Database Development, DB2, Development, Firebird, InterBase, MySQL, OracleDB, PostgreSQL, SQL, SQL Server | Leave a Comment »
Posted by jpluimers on 2017/08/01
Uptime robot (free for 50 monitors every 5 minutes) is cool:
[Archive.is]
[Archive.is]
These are xs4all fiber connections in Amsterdam and Sassenheim. Despite not mentioned on the xs4all status page [WayBack] XS4ALL | Storingen en werkzaamheden, apparently there was some fiber down time in both places.
The HeldenVanNu fiber connection in Amsterdam was doing fine at that time; those downtimes below were planned on my side:
[Archive.is]
–jeroen
Posted in Monitoring, Power User | Leave a Comment »
Posted by jpluimers on 2017/08/01
A very interesting piece of research, in which I see a very familiar concept of single owners and I new concept of them providing shields for accessing the manually managed memory. I do miss mentions of Anders Hejlsberg, Chuck (Charles) Jazdzewski, or others that lay the foundation of ownership in the [WayBack] TComponent Branch.
Microsoft Research’s manual memory management for .NET: https://www.microsoft.com/en-us/research/wp-content/uploads/2017/07/snowflake-extended.pdf
Interesting concept of manual but safe memory management with exactly one owner of an object at any given moment and shields that prevent an object’s destruction while it’s still in use by other threads.
Source: [WayBack] Christopher Wosinski – Google+
–jeroen
Posted in .NET, Delphi, Development, History, Software Development | Leave a Comment »
Posted by jpluimers on 2017/07/31
testssl.sh has supported IPv6 for a long while if the OpenSSL binary supports it
See the below thread, specifically the mentioned comments.
- IPv6 · Issue #11 · drwetter/testssl.sh [WayBack]
- OpenSSL with IPv6 support is needed:
- You need to specify the
-6 parameter or have HAVE_IPv6=true set in HAS_IPv6=true testssl.sh <mycmdline>:
- Special branch of OpenSSL supporting all ciphers (reminder to self: build OS X binaries for it)
- Works with the Google IPv6 site:
- There is still some work to do:
- But the
--ip parameter now supports IPv6 addresses:
–jeroen
Posted in OpenSSL, Power User, Security, testssl.sh | Leave a Comment »
Posted by jpluimers on 2017/07/31
I could not find many potential anti-virus and -malware tools for OpenSuSE Tumbleweed despite they would be useful not only for non-Linux clients like Windows and Mac OS X.
These I found:
–jeroen
Posted in *nix, Linux, openSuSE, Power User, SuSE Linux, Tumbleweed | Leave a Comment »
Posted by jpluimers on 2017/07/27
Not sure why without the -z compression switch this succeeds:
# rsync -avloz /var/lib/named/master/ /etc/named/master/
sending incremental file list
pluimers.com
Segmentation fault (core dumped)
# rsync -avlo /var/lib/named/master/ /etc/named/master/
sending incremental file list
pluimers.com
pluimers.com.20161231
pluimers.com~
sent 10,495 bytes received 74 bytes 21,138.00 bytes/sec
total size is 132,231 speedup is 12.51
# rsync -avloz /var/lib/named/master/ /etc/named/master/
sending incremental file list
sent 1,547 bytes received 13 bytes 3,120.00 bytes/sec
total size is 132,231 speedup is 84.76
–jeroen
via: [WayBack] rsync(1) – Linux man page
Posted in *nix, *nix-tools, Power User, rsync | Leave a Comment »
![[ ]](https://wiert.me/wp-content/uploads/2017/07/compressed.gif)
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