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IF… OR IF… in a windows batch file
...lternative is to use an indicator variable. Initialize it to be undefined, and then define it only if any one of the OR conditions is true. Then use IF DEFINED as a final test - no need to use delayed expansion.
FOR ..... DO (
set "TRUE="
IF cond1 set TRUE=1
IF cond2 set TRUE=1
IF defined TR...
What is the meaning and difference between subject, user and principal?
...ntext of security frameworks, a few terms commonly occur subject , user and principal , of which I have not been able to find a clear definition and the difference between them.
...
Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...s a more complete version that shows more differences between [ (aka test) and [[.
The following table shows that whether a variable is quoted or not, whether you use single or double brackets and whether the variable contains only a space are the things that affect whether using a test with or wit...
MySQL error: key specification without a key length
...r BLOB types such as TINYBLOB, MEDIUMBLOB, LONGBLOB, TINYTEXT, MEDIUMTEXT, and LONGTEXT that you try to make a primary key or index. With full BLOB or TEXT without the length value, MySQL is unable to guarantee the uniqueness of the column as it’s of variable and dynamic size. So, when using BLOB ...
How to parse freeform street/postal address out of text, and into components
We do business largely in the United States and are trying to improve user experience by combining all the address fields into a single text area. But there are a few problems:
...
How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
How can I return pivot table output in MySQL?
...w.artfulsoftware.com/infotree/qrytip.php?id=78
I advise reading this post and adapt this solution to your needs.
Update
After the link above is currently not available any longer I feel obliged to provide some additional information for all of you searching for mysql pivot answers in here. It rea...
Cookies on localhost with explicit domain
...sic thing about cookies. On localhost, when I set a cookie on server side and specify the domain explicitly as localhost (or .localhost). the cookie does not seem to be accepted by some browsers.
...
Is there ever a time where using a database 1:1 relationship makes sense?
I was thinking the other day on normalization, and it occurred to me, I cannot think of a time where there should be a 1:1 relationship in a database.
...
Learning assembly [closed]
... learn Assembly language. The main reason to do so is being able to understand disassembled code and maybe being able to write more efficient parts of code (for example, through c++), doing somethings like code caves, etc. I saw there are a zillion different flavors of assembly, so, for the purposes...